Automated Lawnmower Final Report

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5 Νοε 2013 (πριν από 3 χρόνια και 7 μήνες)

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Participating Members:

Corey Kimble

Colleen Morgan

Erin Radtke

David Smith

Zachary Taylor


EE 481, Senior Design Project


Automated Lawnmower Final
Report



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Abstract

The main objective for the LawnBot

group is to design a lawn mower that incorporates all of the features
from various types of lawn mowers, plus more. The group will create a remote control lawn mower that
utilizes each of the benefits, creating a safe, reliable and user friendly lawn mow
er.

The project was done in
two different stages. The first stage the group completed was the Remote Control Lawn Mower. The second
stage of their project was creating an Autonomous Lawn Mower, the LawnBot.
The remote control lawn
mower has been design
ed and built by many e
ngineers throughout the years.
There are many variations of
the remote control lawn mower, as people across the nation have attempted to advance the basic lawn
mower by implementing the remote control aspect.

The Autonomous Lawn Mow
er was a lot mor
e difficult to
design and build. By integrating hardware and software, the students found just how much technology can
be used to develop an outstanding project.

The group went a step further by creating an even safer version
of the mower
. In addition, the autonomous version is also much more convenient for the user.


Introduction

Mowing the lawn with a standard motor powered lawn mower is an inconvenience, and no one takes
pleasure in it. Cutting grass cannot be easily accomplished by
elderly, younger, or disabled people. Motor
powered push lawn mowers and riding lawn mowers create noise pollution due to the loud engine, and local
air pollution due to the combustion in the engine. Also, a motor powered engine requires periodic
maintenan
ce such as changing the engine oil. Even though electric lawn mowers are environmentally friendly,
they too can be an inconvenience. Along with motor powered lawn mowers, electric lawn mowers are also
hazardous and cannot be easily used by all. Also, if th
e electric lawn mower is corded, mowing could prove to
be problematic and dangerous. The self
-
propelling electric remote control lawn mower is a lawn mower that
has remote control capability. This prototype is robotic user friendly, cost efficient, safe to

use, efficient to
use, and environmentally friendly. It can save significantly on labor costs.

Along with the various ages of users, this lawn mower can also be used by people who have disabilities and
are unable to use a regular push, or riding lawn mower. The prototype will also be automatic and will run on a
charged battery with no cords to inter
fere with operation. This cordless electric lawn mower includes remote
control capability which is less expensive than a robotic lawn mower with sensor capability. This robot lawn
mower design is safe to use. With its remote control capability the lawn mow
er stays within the boundaries
of the lawn because the user is able to have fun control over the lawn mower with the controller. This
prototype is also environmentally friendly. There is no need for gas, oil, and engine to use this device because
it is ele
ctric powered.

The objective of the self
-
propelling electric remote control lawn mower is to extend the design of currently
used lawn mowers, and to improve the capabilities of standard robotic lawn mowers as well as assuring cost
efficiency. This self
-
pr
opelling lawn mower design is comprised of remote control and autonomous capability
that is user friendly so most consumers will be able to use this device. It is safe to use, as well as efficient


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because it electric powered and cordless. With these object
ives mentioned, the self
-
propelling electric
robotic lawn mower is environmentally friendly.





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Table of
Contents

Abstract

................................
................................
................................
................................
.........................

2

Introduction

................................
................................
................................
................................
..................

2

Design Achieveme
nts

................................
................................
................................
................................
....

7

Bumper

................................
................................
................................
................................
.................

7

Invisible Fence

................................
................................
................................
................................
...........

7

RoboRealm

................................
................................
................................
................................
................

7

Remote Control

................................
................................
................................
................................
.........

7

Hardware Design
................................
................................
................................
................................
...........

7

Various Components
................................
................................
................................
................................
.

8

Schematics

................................
................................
................................
................................
................

9

Software Design

................................
................................
................................
................................
..........

14

Communication Setup

................................
................................
................................
............................

14

Initialize

Variables

................................
................................
................................
................................
...

15

Display Drive Motor Values

................................
................................
................................
....................

16

Setup Variable Watch

................................
................................
................................
.............................

16

Button Interface Panels

................................
................................
................................
..........................

16

Setup Test Panel Interface

................................
................................
................................
..................

17

Se
tup Start/Stop Panel Interface

................................
................................
................................
........

18

Main Program Script (VBScript)

................................
................................
................................
..............

18

Battery Check

................................
................................
................................
................................
......

18

Start and Stop Interface Script

................................
................................
................................
............

19

Object/Boundary Detection

................................
................................
................................
................

19

Backup Sequence

................................
................................
................................
................................

19



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Rotate Sequence

................................
................................
................................
................................
.

19

Continue Mowing Sequence

................................
................................
................................
...............

19

Source Code

................................
................................
................................
................................
................

20

Test Results

................................
................................
................................
................................
.................

22

Safety Precautions

................................
................................
................................
................................
......

23

Reflections

................................
................................
................................
................................
..................

24

Appendix 1: User Manual

................................
................................
................................
...........................

24

Introduction

................................
................................
................................
................................
............

24

What’s In the Box?

................................
................................
................................
................................
..

25

Before You

Begin

................................
................................
................................
................................
....

25

Fence Installation Procedure

................................
................................
................................
..................

25

Battery Usage

................................
................................
................................
................................
..........

25

Getting Started

................................
................................
................................
................................
.......

26

How To Mow Your Lawn with the Remote Control

................................
................................
................

26

How to Mow Your Lawn Autonomously

................................
................................
................................
.

26

Safety Features

................................
................................
................................
................................
.......

27

Safety Precautions

................................
................................
................................
................................
..

27

Appendix 2: Maintenance Manual

................................
................................
................................
.............

27

Battery Charge

................................
................................
................................
................................
........

27

Mower Blade

................................
................................
................................
................................
...........

27

Motor Driver

................................
................................
................................
................................
...........

28

Drive Motors

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................................
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................................
...........

28

Wheel Replacement
................................
................................
................................
................................

28

Wire Connections

................................
................................
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................................
...

28



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Relays

................................
................................
................................
................................
......................

29

Appendix 3: Original Design Proposal

................................
................................
................................
.........

30

Appendix 4: Summary of Changes from Original

................................
................................
........................

30

Invisible Fence

................................
................................
................................
................................
.......

171

Battery orientation

................................
................................
................................
...............................

171

Roll
-
ove
r Accelerometer

................................
................................
................................
.......................

171

Bumper

................................
................................
................................
................................
.................

171







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Design Achievements

Bumper

The bumper design combines both safety attributes as well an interfering detection method. The bumper
system is constructed with PVC (polyvinyl chloride) pipe, sheet metal, springs, and push buttons. With a
square design outli
ning the mower with the PVC pipe, the eight spring loaded limbs are designed to touch
push buttons when compressed by the sheet metal bumper. The sheet metal surrounds the PVC to protect
and cover all four sides of the lawn mower. This design is for the mo
wer to stop, go into reverse, and spin
when the push button is compressed by any of the eight bolts attached to the surrounding PVC internal
bumper.

Invisible Fence

The invisible fence system is one that diversifies this robotic lawn mower from any other
project. Using the
magnetic field of a wire entrenched into the ground, a receiver has been integrated into our obstacle
interrupt system to warn the mower of crossing outside of a bounded area. Essentially the same technology
as an electric dog collar,
the electrical pulse that is normally sent to a canine does to the laptop perched onto
the mower.

RoboRealm

The RoboRealm code that this group has developed is used to both control the two motors rotating each rear
wheel along with being the central hub
for all the obstacle interrupt system signals. While the blade is
running, our program sends signals to the each motor determining the speed and direction of the mower.
Upon hitting an obstacle or crossing the threshold of the invisible fence, a signal i
s sent to the laptop via USB
and an interrupt variable is sent. A loop in our RoboRealm program goes through a sequence of stopping the
wheels, going into reverse, and spinning away from the obstacle or toward the bounded area.

Remote Control

The robotic

lawn mower was to be designed with the capability of being controlled both using a laptop
running RoboRealm and a remote control. Integrating The Spektrum DX5e remote control and transmitter
was a process that required elegance in the design by using a s
witch that toggle between remote control or
RoboRealm mode. This remote control can be used to set the direction and speed of the mower. This
addition allows the user both the option for automation and manual controls, which is an essential part of
this
design project.

Hardware

Design




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Various Components

1. Push Mower Body Frame: This was used as the basis of the mower construction. It was modified to handle
t
he other components of the LawnB
ot. The group replaced all four original wheels with two caster

wheels and
two larger wheels that are motor driven.

2. 24 Volt Battery: The battery acted

as a power supply for the LawnB
ot.

3. Safety Switch: The safety switch toggles the 24 volt battery’s connection on/off to the rest of the circuit.
The positive
terminal of the battery is connected to one terminal of the switch while the other terminal is
connected to the main terminal block.

4. Bumper: The physical bumper is made up of an inner square create
d by PVC pipe. The outside has PVC

pipe with attached
sheet metal that is attached to the inner square with
PVC

pipe loaded by a spring. There is
a bolt through each spring connecting the outside and inside layer of the
PVC

pipe. The spring allows the
bumper to compress when the mower has contact with an obje
ct. The bumper also has bolts through it that
are there to activate the pushbuttons.

5. Push buttons: The pushbuttons are attached to the inner square of the
PVC

pipe. They are activated when
the bumper is pushed in and the bolts push them. They let the
program know when an object has come in
contact with the mower. The push buttons are in series with each other and are connected to a serial cable
that connects them to the computer.

6. Plexiglass: The plexiglass is mounted to the mower’s body frame and
allows other components to be
mounted on top of it. It also allows the computer to sit on top of it.

7. Motors: The LawnB
ot has a total of three motors. The blade mower came attached to the mower’s body
frame. Both of its terminals are attached to a spe
cified slot on the main terminal block. The other two
mowers are used to move the wheels of the mower. They are both attached to the mower’s body frame with
two u
-
bolts. The terminals for these two motors are attached to the motor driver’s terminals.

8. M
otor Driver
-

the motor driver is connected to the computer with a serial cable. This allows the program
to dictate the movement of the wheel’s motors.

9. Receiver/Antenna: The
receiver and antenna allow the LawnB
ot to receive communication from a remote
control. The receiver is connected to the motor driver so that the wheel’s motors can be manually driven
using the remote control. The receiver is also connected to relay w
hi
ch allows the motor blade to be
controlled through the remote control.

10. Relay

switches: There are two relay switches. The first, a remote control relay, is attached directly to the
receiver and can be switched when toggled by the remote control. The second relay is connected to the first
and when “switched” allows the connect 24 v
olt battery to power the motor blade. Together the two relay
switches allow the user to activate the mower’s blade using a toggle switch on the remote control.



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11. Computer: The computer stores the program and communicates to various equipment on the
La
wnBot
.
It receives input from the push buttons on the bumper system as well as input from the dog fence receiver.
The computer send
s

output to the all three motors which allows the
LawnBot

to move and to mow.

12. Invisible fence receiver, transmitter, an
d wire: The dog fence receiver sends an output to the computer
program when the mower approaches the dog fence wire. It is connected to the computer with a serial cable.

The schematics page should be referenced for a better understanding of how the comp
onents are electrically
connected.


Schematics



Figure
1
: Final Schematic



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Figure
2
: Motor Driver Schematic




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Figure
3
: Motor Power Schematic






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Figure
4
: Receiver Schematic




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Figure
5
: Relays Schematic



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Software

Design

Communication Setup

The first two processes that the program runs is the initialization of the two communication cables. The first
cable to
be initialized is the serial communication cable. The program RoboRealm already had a feature setup
called “Serial” that created and initialization interface and also governed what went was read in over the
cable and what the program would store that as.


Figure
6
:

Serial Communication Setup in RoboRealm

The figure seen above is what is used to initialize this connection. When the program is started, the
designated communication port is searched for. Once the port is located, the p
rogram initializes module
settings (allowing information to communicate from the cable to the program) and will state if the cable is
connected or not connected. It is from this communication cable that the object avoidance/boundary
detection sensors are f
ed into. The variable used for object/boundary detection was “k”.

The second cable to be initialized is the communication cable that controls the mower drive motors. Just like
the “Serial” connection, RoboRealm also had and initialization setup specificall
y for the motor driver our team
had selected. No programming had to be done to initialize the connection between the computer and the
driver motors. The setup provided searched and found that there were two motors connected to the motor
driver and setup a
range of values for the motors to operate under. The setup also allowed for each motor to
be named a variable to be called later on in the program.



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Figure
7
:

DE Sabertooth Setup in RoboRealm

From the setup, the left drive motor
was labeled “Left_Motor” and the right drive motor was labeled
“Right_Motor”. The setup also initialized the value range of the motors to 1
-
255. For our purposes, 1 is full
power in the forward direction and 255 is full power in the reverse direction. The

value 128 (Midway
between 1 and 255) is the value responsible for stopping the motor.

Initialize Variables

The first set of variables to be initialized are the left and right drive motors. The values of these motors are set
to the stop value (128) which
is then processed by the DE_Sabertooth module in RoboRealm and
automatically sets the motor values on program startup.

The second set of variables to be initialized are the count and state variables used throughout the program.
The variable “c” is used as
a count variable. It is initialized on startup to a value of zero to begin all counting
sequences at zero. This initialization has to be done on startup because the program might have a previous
value of “c” stored in its memory, which would throw mowing t
iming sequences off and could cause a safety
hazard.

The next two variables to be initialized are state variables. The variable “p” is used for the button interface
protocol that pops up when the program is opened. This variable is set to a value of two i
nitially. The
reasoning behind this is that a “p” value of 2 is not used in the program so an initial state of the start and stop
buttons is not defined. When either start or stop is selected from the button interface, the value of “p” is
changed and a scr
ipt program executes the necessary actions. The last initialized variable is the variable “k”.
The variable “k” is used for the object/boundary detection feature of the program. After hours of reviewing
input data when either an object has made contact wit
h the mower, or when the mower gets close to the


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invisible fence, it was determined that “groups” of random values were sent to the computer. Because of the
randomness of the inputs, an arbitrary value of five was assigned to the variable “k” initially.

D
isplay Drive Motor Values

The drive motor values were setup under the “Display_Variable” feature in RoboRealm. These values are
displayed because the state in which the drive motors are in determines the overall direction in which the
lawn mower moves. Thi
s display of variables not only helps the user tell which direction the mower should be
moving in, but it also helps for troubleshooting purposes as well.

Setup Variable Watch

“Watch_Variables” is a feature in RoboRealm that pops up a window that displays

all of the values current
being used and the variables that have been initialized at some point in the program. This window constantly
updates the value of all the variables. This was a very useful tool when creating the program and is a very
helpful aid
when it comes to troubleshooting.

Button Interface Panels


Figure
8
:

Button Configurator

Using the button configurator, two button panel interfaces were created (A test panel and a main start/stop
panel). Within the button
configurator; the name of the button being create, the color of the button, the
color of the text, the position of the button, the size of the button, the variable the button is controlling, the


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value the button with assign to the desired variable, the siz
e of the interface panel, and whether or not the
interface panel pops up when the program is opened can all be edited from this one window.

Setup Test Panel Interface


Figure
9
:

Test Panel Interface

This test panel was initially

created for the help in creating the program and troubleshooting. This panel was
left in the final program because of the troubleshooting ability it has. This panel does not pop up when the
program is opened; it was created for sole troubleshooting purpos
es.

At the top of the interface, there are four buttons. These buttons all are used for setting certain states to the
main variables used in the program. The “c Reset” button resets the value of the c variable to a value of zero.
This proved useful when de
termining how many seconds elapsed when c reached a certain value. The “k
Reset” button was used to simulate receiving an object/boundary detection signal. Because during the testing
of the program, the mower was not available at all times (nor was it nece
ssary to have the drive motors
continuously running during the tests), the “k Reset” button allowed for the test of the object/boundary
detection scripts without the need of being connected to the mower. The “j Set” and “j Reset” buttons allow
for state in

which the object/boundary detection process is currently in to be changed. This helped out
tremendously when troubleshooting the main code for this project.

The remaining six buttons are for control of the drive motors. The three buttons on the left cont
rol the left
drive motor and the three buttons on the right control the right drive motor. The top buttons allow for the
motors to be set in the forward state “1”. The middle buttons allow for the motors to be stopped “128”. And
the last buttons allow for
the motors to be set in the reverse state “255”. This part of the panel came to great
use when the drive motors were installed and were being tested with the program for the first time. These
buttons were left in the program after the motors had been fully

tested because of the secondary use. These
buttons allow for a user to hold the computer and drive the mower solely from the computer. This allows an


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individual to drive the mower back to their garage per say after the mower is done mowing without having
to
switch to the remote control mode or carrying the mower.

Setup Start/Stop Panel Interface


Figure
10
:

Start/Stop Panel Interface

This panel interface is much simpler than the test panel previously discussed. The purpose of th
is panel is to
be the main interface tool for the project. This panel pops up in the middle of the screen as soon as the
program is opened. The user is to simply hit the start button and the mowing process will commence and the
program will do all of the w
ork. The stop button was added for the sake of a way to stop the mowing process
when needed (The mower is not very fast and easy to access even during the mowing process).

T
he start button simple sets both of the drive motors to their forward value “1” an
d the stop button sets both
drive motors to their stopped value “128”.

Main Program Script (VBScript)

RoboRealm continuously loops through itself. Because of this, the main processes of this program had to be
broken up into individual scripts in order for
them to be executed properly. For the actions needed to be
performed by the mower for this project, there were six main script programs that needed to be created.

Battery Check

The battery check program checks the percent of battery that the computer has
left. If the computer were to
run out of power before the mower was done, the mower would continue mowing on a straight path because
the object/boundary detection systems would not be able to be recognized. This would probably not only
cause damage to the
mower itself, but cause damage to others property and bring harm towards any
individual caught in its path. To combat this issue, if the battery power is less than 10%, the drive motors are
set to their stopped state. This will allow for the mower to be ap
proached safely and for the computer to be
detached and charged.



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Start and Stop Interface Script

This script is for the “Start/Stop Interface Panel”. Because a button can only control one variable at a time,
there was the need to control both drive moto
rs simultaneously. In order to do this, the variable “p” was
used. When the start or stop button is pressed on the panel, the value of “p” is changed. This script then
determines whether the start or stop button was pressed. If start was pressed, both driv
e motors are set to
the forward state “1”. If stop was pressed, both drive motors are set to the stop state “128”. The value of p
then has to be reset at the end of the script in order to prevent an endless loop from occurring.

Object/Boundary Detection

T
his script is the most important and surprisingly the smallest part of the entire program. The program has to
read in the value received from the input serial connection (Which is the value received from the bumper
switches and the invisible fence shock c
ollar) and store it into a variable, “k”. That variable then has to be
checked for any change. Once that variable has changed, the drive motors are stopped and the next state of
the object/boundary detection is set. The variable “k” is then reset to its no
rmal state so that any other
change can be detected.

Backup Sequence

The count variable and the state variable are read into the script and stored in respective spaces. The backup
sequence is only executed if the correct state value is set from the previo
us set of code. If the correct state is
set, then the count variable is incremented until a designated value is reached. Once the designated value is
reached (Creating a time delay feature), the drive motors are switched from their stopped positions to
re
verse positions. The motors will remain in this state until the next sequence of code is analyzed. After the
drive motors are set to reverse, the state variable is changed so the next task can be executed and the count
variable is reset to zero.

Rotate Seq
uence

Just like the backup sequence, the count and state variable are read into the script and stored. If the correct
state is present, then the count variable is incremented again until its designated value. The confusing aspect
of this whole process is that th
e length in which the drive motors remain in a certain state are based off of the
following sequence (I.E. The motors are stopped for as long as the time delay located in the backup sequence
is. The drive motors are in reverse for the length of the time de
lay designated in this sequence, etc…). Once
the designated count value is reached, the left drive motor is set to remain in reverse and the right drive
motor is set to the forward state. This will cause the mower to perform a zero turn (Pivot based off th
e center
of the mower), rotating away from the object/boundary the mower just encountered. The state variable is
changed to perform the next task and the count variable is reset to zero.

Continue Mowing Sequence

Finally, the count and state variables are

read into the script and stored. If the correct state is present, the
time delay count variable is incremented until the designated value is reached. Both drive motors are then set


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to their forward states so that the mower can continue mowing in a differe
nt direction. The state variable is
reset to zero as well as the count variable.

Source Code

Initialize Variables

Set Left_Motor = 128

%Initializes the left drive motor to 128 (Stopped)

Set Right_Motor = 128

%Initializes the right drive motor to 128 (Stopp
ed)

Set p = 2
% The value p is used to start and stop the motors through the Start Stop Interface

Set k = 5
% The value k is used as the variable which object/boundary detection is determined

Set c = 0
%The value c is used as a count variable


Check
Battery Power

W = GetVariable("POWER_LIFE_PERCENT")

%St
ores the value of the computer battery power


if W<10 then

%Creates “If
-
Then” Statement to check if battery power is less than 10%

SetVariable "Right_Motor", 128

%If the battery power is less tha
n 10% set right drive motor to stop

SetVariable "Left_Motor", 128

%If the battery power is less than 10% set left drive motor to stop

end if



Start and Stop Button Interface

p = GetVariable("p")
%Retrieves and stores the value of p


if p = 1 Then

%

“If
-
Then” Statement checking the value of p

SetVariable "Left_Motor", 1

%If
p is equal to 1 then
set left

drive motor to forward

SetVariable "Right_Motor", 1

%If
p is equal to 1 then set right drive motor to forward

end if



if p = 0 Then

%

“If
-
Then” Statement checking the value of p

SetVariable "Left_Motor", 128

%If
p is equal to 0 then
set left

drive motor to stop

SetVariable "Right_Motor", 128

%If
p is equal to 0 then
set left

drive motor to stop

end if


SetVariable "p", 2

%
Resets t
he value of p to 2 so a never ending loop is not created


Object/Boundary Detection

k = GetVariable("k")

%
Retrieves and stores value received from bumper or invisible fence sensor

if k <> 5 then

%
Checks to see if k is not equal to 5

SetVariable "Left_M
otor", 128

%

If
k is not equal to 5 then
set left

drive motor to stop



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SetVariable "Right_Motor", 128

%

If
k is not equal to 5 then set right drive motor to stop

SetVariable "j",3

%
Set state variable j to 3

end if

SetVariable "k", 5

%

Resets the val
ue of k to 5 so a never ending loop is not created

Backup Sequence

c = GetVariable("c")

%Retrieves and stores the value of c

h = GetVariable("h")

%Retrieves and stores the value of h

j = GetVariable("j")

%Retrieves and stores the value of j


if
j = 3

then

%Checks to see if the state of j is equal to 3

h = c + 1

%Increments the count variable by one and stores the value in h

SetVariable "c", h

%Sets the value of c to the value stored in h

if c = 50 then

%Checks to see if c is equal to 50

SetVar
iable "Left_Motor", 255

%Sets left drive motor to reverse


SetVariable "Right_Motor", 255

%Sets right drive motor to reverse

SetVariable "j", 4

%
Sets state variable j to 4

SetVariable "c", 0

%
Sets count variable c to 0

end if

end if


Rotate
Sequence

c = GetVariable("c")

%Retrieves and stores the value of c

h = GetVariable("h")

%Retrieves and stores the value of h

j = GetVariable("j")

%Retrieves and stores the value of j


if j = 4
then

%Checks to see if the state of j is equal to 4

h =

c + 1

%Increments the count variable by one and stores the value in h

SetVariable "c", h

%Sets the value of c to the value stored in h

if c = 50 then

%Checks to see if c is equal to 100

SetVariable "Left_Motor", 255

%Sets left drive motor to rever
se


SetVariable "Right_Motor", 1
%Sets right drive motor to forward

SetVariable "j", 4

%
Sets state variable j to 5

SetVariable "c", 0

%
Sets count variable c to 0

end if

end if


Continue Mowing Sequence

c = GetVariable("c")

%Retrieves and stores the

value of c

h = GetVariable("h")

%Retrieves and stores the value of h

j = GetVariable("j")

%Retrieves and stores the value of j



22

|
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if j = 5

then

%Checks to see if the state of j is equal to 5

h = c + 1

%Increments the count variable by one and stores

the value in h

SetVariable "c", h

%Sets the value of c to the value stored in h

if c = 50 then

%Checks to see if c is equal to 200

SetVariable "Left_Motor", 1
%Sets left drive motor to forward


SetVariable "Right_Motor", 1
%Sets

right drive motor to forward

SetVariable "j", 0
%
Sets state variable j to 0

SetVariable "c", 0

%
Sets count variable c to 0

end if

end if

Test Results

The LawnBot was tested in two different environments, indoors
and outdoors.
The LawnBot was first

an
d
mostly

tested
indoors with

the remote control

components
.
The testing occurred throughout the
construction process. As a new component was added to the system it was tested

independ
en
tly

to make
sure it worked as desired as well as
working in
the system
as a whole.
The motors, relay, computer, and
software were all tested separately as each component was added until each component was working
properly.

The group was very successful
during t
his first stage of the LawnBot testing with only a few minor
nega
tive tests. One such occurrence was with the first relay switch. The switch was designed specifically for
use of remote control but was not rated for a high current. When tested, the group found the current the
blade motor drew was not over the rated curre
nt, however when first started the blade motor drew a current
which burned out the relay after a few uses. To address this issue, the group added a second relay, which was
not specifically designed for remote control use but could handle a much larger curr
ent than the first relay.
The first rel
a
y would still
be required to

be used but would not draw the current from the battery, only
activate the second relay which then allowed the blade motor to operate at the current it needed to start.

This was successf
ully tested indoors as one could hear the relays activate when the toggle switch was
engaged on the remote control, without having the blade motor connected to the relay for indoor safety
precautions.

The group then attempted testing in an outdoor
environ
ment with the remote control to ensure that the
LawnBot was able to cut grass.

The group was eventually successful, but it required more effort mechanically
to complete this stage
to address issues such as environmental inclines
.
T
he group was able to cut

the grass
successfully o
utdoors with the remote control after the changes were made.

The second stage of the testing involved controlling the mower autonomously indoors and outdoors.

By
doing so, the group used the program RoboRealm
to communicate with the integrated mowing system.

Along with this program, the group used an invisible fence for boundary detection, and a bumper system for
object interference detection.

When the LawnBot was tested indoors autonomously with the invisibl
e fence,


23

|
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the group was successful.

However, the group ca
me across several difficulties that were mostly program
related at this
stage.
After configuring the program to work well with the invisible fence and the bumper
system’s push buttons, the mower app
eared to run smoothly indoors.

Once the LawnBot was tested successfully indoors, the group tested the Lawn
Bot outdoors. The group

ca
me
across several difficulties

that were not issues indoors
. F
irst, the bumper system fell apart within t
he first
twenty m
inutes of use.
Unfortunately, this was not a

quick fix for the bumper team.
The group needed to
reconstruct a more stable bumper that would cooperate in West Virginia’s uneven

terrain.
With

higher
patches of grass, the caster wheels bogged down
. When t
he mower was at a level surface, it cooperated
perfectly. Because of the high torque motors, the LawnBot operated at the same speed no matter the incline.
Additionally, another issue occurred when the remote control receiver and the cables connecting to
the
computer were both connected to the motor driver. Both were successful during testing when connected
independently, but having both connected simultaneously, caused communication issues. A switch was
added to toggle back and forth between the remote
control and computer. Another issue that occurred
when testing was only having one serial cable for the push buttons and invisible fence. The push buttons and
invisible fence could be read into the program, but the motors could not b
e controlled at the s
ame time. To
fix this, the group added a second serial cable, which allowed both the buttons and invisible fence to be
connected simultaneously.

As previously mentioned
, with time the LawnBot proved to be successful with remote control capability
indoors
and outdoors. The LawnBot also proved to be successful autonomously indoors and outdoors.
However, the LawnBot acted more temperamental during autonomous use

especially when used outdoors in
less controlled environments
.


Safety Precautions

Safety is a
primary concern for the robotic lawn mower. The mower has two different types of kill switches
that play an important role in the safety aspect of the mower. The first is a mower blade kill switch which is
located on the remote control to stop the blade.

This switch is a user operated switch and could be used in
the event of an
emergency

situation. There also is a manual kill switch that is located on the mower to turn
off the mower for storage. Lastly,
a bumper

was constructed onto the mower which

det
ects when there is a
foreign object in the mower’s path.

With these safety features, users still must take precautions when using this lawn mower. The lawn mower
has a sharp blade that shou
ld not be operated by children.
Users should remove any objects f
rom the lawn
that may cause interf
erence to the mower before use.
Users should not use this lawn

mower around pets or
children.
Users should not operate electric lawn mower in standing wat
er or during inclement weather.
The
lawn mower should only be use
d on a grass
y area.
Users should take precautions when installing invisible
fence
.
Do not operate lawn mower unsupervised.



24

|
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Future builders must take prec
aution when assembling mower.
Blades are sharp and could cause harm to
assemblers. The sheet metal
bumper has shar
p edges and could cause injury.
Also,
future builders should
be
sure to disconnect the mower from the voltage source when wiring.

Reflections

Overall, constructing the lawn mower was a success. However, there were a few details that were
not
constructed that had been originally planned. In addition, there were things that would have been changed
from the beginning that would have made this project much easier. First, the group consisted of five
electrical engineering students. The group

should have had a few electrical engineering students, a few
computer science students, and a computer engineering student. The electrical engineering students could
have focused solely on the hardware. The computer science students would have had a lot

more experience
with programming and would have been able to develop

the software design in a more efficient way
. Lastly,
the computer engineering major would have been able to integrate the software and hardware in a much
easier manner.

Secondly,
t
he group also felt that RoboRealm was not the best choice of software for the LawnBot.
RoboRealm is used mainly for digital image processing

purposes
. The LawnBot group used this software
solely for providing outputs given the inputs. The signal would c
ommunicate with the lawn mower after the
mower had come into contact with the invisible fence. Nothing with the RoboRealm software was used for
image analysis. The group would have found a different programming language that was less complex
considering
there were only a few input commands.

Lastly, given the am
ount of money that was provided, the
mower was not constructed as well as it could have
been.
The group
was not able to obtain
higher quality power tools than the tools that were used. If better
c
onstructing equipment was supplied to the group, the mower would have cosmetically appeared more
professionally constructed. For instance, the group had a difficult time properly cutting the PVC pipe to the
accurate measurements. Also, if more money had
been provided to the group, a Global Positioning System
(GPS) could have been used for the boundary detection instead of the invisible fence. This system is more
accurate than the invisible fence. If the GPS sy
stem was installed and used correctly, it wo
uld have been
more successful
in the boundary detection area. The invisible fence’s program became a tedious process to
complete, and the fence overall was temperamental. In addition, had the GPS been provided, the lawn itself
would have cosmetically app
eared much better after a fresh cut.

Appendix 1:
User Manual

Introduction

No one wants their lawn mower to stray into a neighbor's yard, in

the street, or even into a flower bed. In
visible fence gives your lawn mower freedom to roam within set boundaries and gives you peace of mind.



25

|
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What’s In the B
ox?

The materials that are located in the package are the LawnBot, 24V DC battery, battery char
ger, remote
control, and invisible fence.

Before You B
egin

Plot your yard on a piece of paper and draw in the area you want to cover. In several instances corners must
be rounded. The wire forming the fence boundary must make a continuous loop back to the

transmitter. The
invisible fence must be buried 1 inch to 3 inches underground. Test your wires aboveground before burying
them.

Precautions when installing Invisible Fence



Be sure to burry fence with care. Invisible fence should not be buried with electr
ical wires, telephone
wires, television cables, antenna wires or near satellite dishes. Avoid crossing power lines.




If you plan to cross a gravel or dirt driveway, protect your wire by running it through polyvinyl
chloride (PVC) pipe.



Avoid running the b
oundary wire close to chain
-
link fences.

Fence I
nstallation

Procedure


Step 1
:

Referring to the plot you created, lay the wire along your proposed boundary.


Step 2
:

Connect the ends of the boundary wires to the transmitter, and turn the system on.


Step
3
:

Test the transmitter on the LawnBot to ensure it's working properly. The LawnBot should emit an audible
alert as you near the boundary.


Step 4
:

Begin cutting a trench 1 inch to 3 inches deep along your previously planned boundary. Lay the invisible fen
ce
in the trench and burry it.


Battery Usage

Be sure to charge

24V battery with the battery ch
arger for 24 hours before installing in the LawnBot.




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|
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Getting Started


Figure
11
: Remote Control

Once battery is charged, insert it into the LawnBot. Turn the On/Off switch to the On position to ensure that
the LawnBot is powered.

How

To Mow Your Lawn with the Remote Control

While the LawnBot is turned Off se
t the dip switch to the remote control position. Turn ground switch into
remote control position. Turn the On/Off switch in the On position on the Lawn Bot. Place LawnBot within the
area you wish to mow. Turn the On/Off switch on the remote control in the
On position. The blade activation
switch must be engaged while using the right wheel and left wheel switch. You may now start mowing the
lawn using the remote control. When finished turn both switches in the Off position.

How to Mow Your Lawn Autonomously

While the LawnBot is turned Off set the dip switch to the autonomous position. Turn ground switch into
autonomous position. Turn the On/Off switch in the On position on the Lawn Bot. Place LawnBot within the
boundaries of the invisible fence. Press “start
” on the computer program. Now allow LawnBot to mow the
designated area. The battery has 60 minutes of po
wer usage. When battery is dead, the LawnBot will
come
On/Off Switch


Blade Activation Switch


Left Wheel


Right Wheel



27

|
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to a complete stop. If your lawn is not completely mowed, recharge the battery, until it is com
pletely charged,
and repeat the mowing process.

Safety Features

The mower has two different types of On/Off switches that play an important role in the safety aspect of the
mower. The first is a mower blade On/Off switch which is located on the remote con
trol to stop the blade.
This switch is a user operated switch and could be used in the event of an emergency situation. There also is
an On/Off switch that is located on the mower. Lastly, a bumper was constructed onto the mower which
detects when there
is a foreign object in the mower’s path. When the bumper comes in contact with a foreign
object, when in autonomous mode, the LawnBot with stop and reroute itself.

Safety Precautions

-

Warning! The lawn mower has a sharp blade and could cause injury
.

-

The Law
nBot should not be operated by children.

-

Be sure to remove any objects from the lawn that may cause interference to the mower before use
.

-

Do not use this lawn mower around pets or children
.

-

Do not operate electric lawn mower in standing water or during i
nclement weather
.

-

Only use LawnBot on a grass
.

-

Do not operate lawn mower unsupervised
.

-

Do not attempt to turn the LawnBot off while it is in the autonomous mode
.

Appendix 2:
Maintenance Manual

This manual is for the upkeep and reference manual for the
robotic lawn mower. Within this manual, simple
part fixes will be discussed as well as routine mower maintenance.

Battery Charge

The entire mower relies on the battery being charged. There is a battery gauge located on top of the battery
itself. Three ligh
ts means that the battery is fully charged, two lights means there is at least half the battery
left, and one light means that the batter is low and needs recharged. The mower should not be operated if
the battery is lower than two lights of charge. The ba
ttery should be charged every time before each time the
mower is to be used, using the provided charging cable. If the

Mower Blade

The blade located on this mower is l
ike

the blade on any regular lawn mower. This mower will accept any
regular 14” (14 inc
h) mower blade. Here are a few steps to check on the sharpness of the mower blade:



Ensure that the mower is turned off and remove the battery



Tilt the lawn mower on its side to reveal the undercarriage of the mower



Loosen nut holding blade in place and rem
ove blade



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|
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Inspect the sharpness of blade (Doesn’t need to be razor sharp but still needs an edge)



If blade is dull, e
ither buy new blade or sharpen
the
old blade



Replace blade and tighten nut



Place mower upright and re
-
insert battery

Motor Driver

The
motor driver is a self
-
contained unit that controls the voltage provided to the drive motors. When the
power for the mower is on, there should be one dim blue light on the motor driver. Any errors or issues with
the motor driver will result in a flashing r
ed light or a no light at all. In either case, first check all connections
leading to the motor driver and tighten any loose connections. If this does not fix the error please contact the
following:

Email:

sup
port@dimensionengineerin.
com

Phone:

(330)
634
-
1430

Fax:

(330) 634
-
0215

Hours:

9AM to 7PM Eastern Time

Mail:

Dimension Engineering

899 Moe Drive #21

Akron, OH 44310

Drive Motors

Since these are electric motors, they require no routine maintenance.

If the drive motors are not working properly, first check the motor connections. If that is not the problem
check the connection between the remote control and the receiver or the communication connection
between the computer and the motor driver. If there

is no connection issue, ensure that the battery is fully
charged. If the motors still do not respond, they will need to be replaced.

http://www.phidgets.com/products.php?category=24&product_id=3273_0

Wheel Replacement

The front wheels are simple 2” (2 in
ch) caster wheels that can be purchased at any hardware store if the
wheels are damaged or just need replaced. The larger rear wheels are located at the following address:
http://www.andymark.com/product
-
p/am
-
0514.htm
. If a back wheel needs replace (broken

spokes or hub),
remove the cotter key from the hub, slide old wheel off, slide new wheel on and replace cotter key. If the
tread is low on the tires, new tread can also be purchased from andymark and instructions for installation will
be included

Wire Con
nections

Any wire connection that deals with a motor or 24v power is 12 AWG wire. Any wire connection that deals
with communication is 20 AWG wire. If any wire appears to be damaged, replace entire wire.



29

|
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Relays

If the mower blade will not spin, it is most

likely a relay issue. Listen to each relay when they are energized to
hear a “click”. If there is no “click” then the relay is either bad or there is a loose connection. Check the
connections going to and from the relays. If this does not fix the issue th
en the bad relay(s) will need to be
replaced. The large relay can be replaced with any 24v ice cube relay that can withstand anything over 10
amps. The smaller relay will need to be replaced with another D
imension Engineering

Battle Switch:
http://www.dime
nsionengineering.com/products/battleswitch
.





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|
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Appendix 3: Original Design Proposal









D
e
s
ig
n

P
r
o
p
o
s
a
l

f
or

t
h
e

L
a
wn
B
o
t



Cha
n
g
ing

t
he way you

m
ow

yo
u
r

g
r
ass

s
i
n
ce

2012
.





Pa
r
t
icipat
in
g

Mem
b
e
r
s:

Cor
e
y

K
imb
l
e

Colle
e
n

M
o
r
g
a
n

Er
i
n

R
a
dtke
D
a
vid

S
m
ith

Zachary

T
a
y
lor




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|
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April 2012


32

|
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Contents

1.

Extended Problem Statement

................................
................................
................................
............

38

1.1.

Need

................................
................................
................................
................................
...........

38

1.2.

Objective

................................
................................
................................
................................
....

39

1.3.

Background

................................
................................
................................
................................

40

1.4.

Stakeholder goals

................................
................................
................................
.......................

42

1.5.

O
bjective Tree

................................
................................
................................
............................

43

1.6.

Ranking of Needs

................................
................................
................................
.......................

43

2.

Re
q
u
i
rem
e
n
t
s

S
pec
i
f
i
c
a
t
i
o
n

................................
................................
................................
...............

45

2.1.

F
u
nc
t
i
o
n Descriptions

................................
................................
................................
................

45

2.1.1.

Added Com
p
o
n
e
n
t

F
u
n
ct
i
o
n
s

................................
................................
............................

45

2.1.1.1.

Recha
r
gea
bl
e Bat
t
eries f
o
r

Added C
o
m
p
o
n
e
n
t
s
................................
............................

45

2.1.1.2.

Deadman

s

K
i
ll
s
w
i
t
ch

................................
................................
................................
.....

45

2.1.1.3.

Tu
r
n

Over

Kil
l
s
w
i
t
ch

................................
................................
................................
.......

45

2.1.1.4.

Se
n
s
o
r

................................
................................
................................
............................

45

2.1.1.5.

Ze
r
o

Tu
r
n

Fu
n
ct
i
o
n

................................
................................
................................
.........

46

2.1.1.6.

G
r
a
s
s

C
l
ippi
n
g

Catc
h
er

................................
................................
................................
...

46

2.1.2.

2
.

Re
m
o
t
e Co
n
t
ro
l

Fu
n
c
t
ions

................................
................................
.............................

46

2.1.2.1.

Remote Control/Transmitter

................................
................................
.........................

46

2.1.2.2.

Remote

En
ga
g
em
e
n
t

................................
................................
................................
......

46



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|
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2.1.2.3.

Receiv
e
r

................................
................................
................................
..........................

46

2.1.3.

M
ow
er

Fu
n
ct
i
o
n
s

................................
................................
................................
...............

47

2.1.3.
1.

M
ow
i
n
g A
b
ility

................................
................................
................................
...............

47

2.1.3.2.

S
elf
-
P
ro
pul
s
i
o
n

................................
................................
................................
...............

47

2.1.3.3.

El
ec
t
r
ic

Mo
w
er

................................
................................
................................
...............

47

2.1.
4.

Automation

Fu
n
c
t
ions

................................
................................
................................
........

47

2.1.4.1.

Self
-
Controlled

................................
................................
................................
...............

47

2.1.4.2.

Battery Detection

................................
................................
................................
...........

47

2.
1.4.3.

Boundary Detection

................................
................................
................................
.......

48

2.2.

Req
u
i
r
em
e
nt
s

................................
................................
................................
.........................

48

2.2.1.

M
ark
e
t
i
n
g Req
u
i
r
em
e
nt
s

................................
................................
................................
...

48

2.2.2.

E
n
gi
n
e
e
r
i
n
g
R
e
q
uirem
e
nt
s

................................
................................
................................
.

49

2.2.3.

Market / E
n
gi
n
e
e
r
i
n
g
R
e
q
uirem
e
nt

Trade
-
off

................................
...............................

50

2.3.

C
o
m
p
e
t
i
t
i
v
e

Benc
h
marks

................................
................................
................................
...........

51

2.3.1.

C
o
n
str
a
i
nt
s

................................
................................
................................
.........................

51

2.3.1.1.

E
c
o
n
o
mic

................................
................................
................................
........................

51

2.3.1.2.

E
n
viro
n
m
e
nt
al

................................
................................
................................
................

51

2.3.1.3.

E
t
hical

a
n
d L
e
g
al

................................
................................
................................
............

52

2.3.1.4.

H
ea
l
t
h
a
n
d
S
afe
t
y

................................
................................
................................
...........

52

2.
3.1.5.

M
a
n
ufa
c
t
u
r
a
b
i
l
i
t
y

................................
................................
................................
...........

52



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|
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2.3.1.6.

P
o
l
i
t
ical

................................
................................
................................
...........................

52

2.3.1.7.

S
o
cial

................................
................................
................................
..............................

52

2.3.1.8.

S
ustai
n
a
b
ility

................................
................................
................................
..................

53

2.3.2.

S
t
anda
r
ds

................................
................................
................................
...........................

53

2.3.2.1.

S
af
e
t
y

................................
................................
................................
.............................

53

2.3.2.2.

D
a
t
a

F
or
mats

................................
................................
................................
..................

53

2.3.2.3.

Pr
o
gr
a
mm
in
g

Lan
g
uages

................................
................................
................................

53

2.3.2.4.

Me
ta
-
Sta
n
da
r
d
s

................................
................................
................................
.............

54

3.

System Design

................................
................................
................................
................................
....

55

3.1.

Scope

................................
................................
................................
................................
..........

55

3.2.

Context Diagr
am

................................
................................
................................
........................

56

3.3.

First Stage: Remote Control

................................
................................
................................
.......

57

3.3.1.

Basic Operations

................................
................................
................................
................

57

3.3.1.1.

Electric Lawn Mower Base

................................
................................
.............................

57

3.3.1.2.

Remote Control Transmitter and Receiver

................................
................................
....

57

3.3.1.3.

Motor Driver

................................
................................
................................
..................

58

3.3.1.4.

Rear Motors

................................
................................
................................
...................

58

3.3.1.5.

Caster Wheels

................................
................................
................................
................

58

3.3.1.6.

Miscellaneous

................................
................................
................................
................

58

3.3.1.

Wiring Diagram

................................
................................
................................
..................

59

3.3.2.

Remote Control Interface

................................
................................
................................
..

60



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|
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3.3.2.1.

Kill Switch

................................
................................
................................
.......................

60

3.3.2.2.

Left Motor Control

................................
................................
................................
.........

60

3.3.2.3.

Right Motor Control

................................
................................
................................
.......

61

3.3.3.

Functions of Overall Operation

................................
................................
..........................

61

3.3.4.

Testing

................................
................................
................................
................................

62

3.4.

Second Stage: Automation
................................
................................
................................
.........

63

3.4.1.

Basic Operations

................................
................................
................................
................

63

3.4.2.

Sensors

................................
................................
................................
...............................

63

3.4.2.1.

Tilt Sensor

................................
................................
................................
.......................

63

3.4.2.2.

Object Avoidance

................................
................................
................................
...........

64

3.4.2.3.

Range Sensor

................................
................................
................................
..................

64

3.4.3.

Processor

................................
................................
................................
............................

64

3.4.4.

Computer

................................
................................
................................
...........................

65

3.4.5.

Programming
................................
................................
................................
......................

65

3.4.5.1.

RoboRealm

................................
................................
................................
.....................

65

3.4.5.2.

Dog Fence Boundary

................................
................................
................................
......

66

3.4.5.3.

GPS Boundary

................................
................................
................................
.................

66

3.4.5.4.

Trace and Record Boundary

................................
................................
...........................

67

3.4.6.

Testing

................................
................................
................................
................................

68

4.

SOFTWARE TESTS

................................
................................
................................
...............................

69

4.1.

Remote Control


Transmitter Signal
................................
................................
.........................

69



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4.2.

Mower Orientation

................................
................................
................................
....................

69

4.3.

Battery Power

................................
................................
................................
............................

70

4.4.

Obstacle Sensor

................................
................................
................................
.........................

71

4.5.

Act
ive Blade

................................
................................
................................
...............................

72

4.6.

Mobility

................................
................................
................................
................................
......

75

4.7.

Direction of Motion

................................
................................
................................
...................

78

5.

Project Plan

................................
................................
................................
................................
........

81

5.1.

Project Management

................................
................................
................................
.................

81

5.1.
1.

Preliminary Work Breakdown

................................
................................
............................

81

5.1.2.

Project Timelines
................................
................................
................................
................

82

5.1.3.

Budget

................................
................................
................................
................................

84

5.2.

Q
u
a
li
f
i
c
a
t
i
o
ns

................................
................................
................................
.............................

86

5.2.1.

C
or
ey

Kimb
l
e

................................
................................
................................
......................

86

5.2.2.

C
oll
e
e
n

M
or
gan

................................
................................
................................
..................

86

5.2.3.

Er
in

R
a
d
t
k
e

................................
................................
................................
.........................

86

5.2.4.

D
a
v
id

S
mi
t
h

................................
................................
................................
........................

87

5.2.5.

Z
a
c
ha
r
y Tay
lo
r

................................
................................
................................
....................

87

6.

Re
f
erenc
e
s

................................
................................
................................
................................
.........

88

Appendix A: Individual Reports

................................
................................
................................
.................

90

Corey Kimble

................................
................................
................................
................................
..........

90

Colleen Morgan

................................
................................
................................
................................
....

102



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Erin Radtke

................................
................................
................................
................................
...........

118

David Smith

................................
................................
................................
................................
..........

137

Zachary Taylor

................................
................................
................................
................................
......

152





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1.

Extended Problem Statement

1.1.

Need

Mowing the lawn with a standard motor powered lawn mower is an inconvenience,
and no one takes pleasure in it. Cutting grass cannot be easily accomplished by elderly,
younger, or disabled people. Motor
powered push lawn mowers and riding lawn mowers

create noise pollution due to the loud engine, and local air pollution due to the combustion
in the engine. Also, a motor powered engine requires periodic maintenance such as
changing the engine oil. Even tho
ugh electric lawn mowers are environmentally friendly,
they too can be an inconvenience. Along with motor powered lawn mowers, electric lawn
mowers are also hazardous and cannot be easily used by all. Also, if the electric lawn
mower is corded, mowing coul
d prove to be problematic and dangerous. The self
-
propelling electric remote control lawn mower is a
lawn mower that has remote control
capability. This prototype is
robotic user friendly, cost efficient, safe to use, efficient to
use, and environmentally

friendly.
It can save significantly on labor costs.
Along with the
various ages of users, this lawn mower can also be used by people who have disabilities
and are unable to use a regular push, or riding lawn mower.

The prototype will also be
automatic

and

will
run on a charged battery with no cords to interfere with operation.

This
cordless electric lawn mower includes remote control capability which is less expensive
than a robotic lawn mower with sensor capability. This robot lawn mower design is safe to

use. With its remote control capability the lawn mower
stays within the boundaries of the
lawn because the user is able to have fun control over the lawn mower with the controller.
This prototype is also environmentally friendly. There is no need for gas,

oil, and engine to
use this device because it is electric powered.



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Figure
12
: Needs of Overall Project

1.2.


Objective

The objective of the
self
-
propelling electric remote control lawn mower is to

extend the
desig
n of currently used
lawn mowers, and to improve the capabilities of standard robotic lawn
mowers as well as assuring cost efficiency.

This self
-
propelling lawn mower design
is comprised
of remote control capability that is user friendly so most consumers will be able to use t
his
device. It is safe to use, as well as efficient because it electric powered and cordless. With
these objectives mentioned, the self
-
propelling electric robotic lawn mower is environmentally
friendly.

The
first
expected

outcome for this project is
th
e creation of a lawn mower that will cut via

remote control, and then adapt that design to create a mower to operate autonomously
. There


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are already robotic lawn mowers in production, however, they are not
readily
abundant and
are expensive. The
primary go
al
is to create a reliable and efficient robotic lawn mower that is
not expensive to
build
and performs well.

The purpose of this project is
to alter the already
built lawn mower in
such a way that minimal effort will be required to perform the task of
mow
ing grass.
This incorporates designing all of the features necessary to perform all the tasks
posed for this lawn mower to accomplish. Once a final design has been created to the
standards agreed on by the group, parts for the mower will then have to be ob
tained. The final
design will incorporate communication between both hardware and software components.
The two main aspects of the project needed to be accomplished is the overall safety of the
machine itself and the effectiveness to efficiently cut grass.

The next objective is to automate the mower
so that the us
er is taken out of the picture,
and the user’s only task is
setting up the device initially
. T
he
primary objective is to obtain a
finished product
that
will help further advance the mowing industr