PPT 7 - Adaptive Structure

jabgoldfishΤεχνίτη Νοημοσύνη και Ρομποτική

19 Οκτ 2013 (πριν από 3 χρόνια και 9 μήνες)

72 εμφανίσεις


Robotics/Machine Vision


Robert Love, Venkat Jayaraman


July 17, 2008

SSTP Seminar


Lecture 7

Overview


Presentation


Parts of a Robot


Robotics Components


Joints and Linkages


Actuators


Sensors


Controller


Machine Vision


Basic Theory, Application: Harvesters


Image processing


Aircraft Control, Bonding


Visual Image Correlation, Photogrammetry


Discussion


Activity

10/19/2013

UF Flight Controls Lab

2

Parts of a Robot

10/19/2013

UF Flight Controls Lab

3


Body


Effectors


Actuators


Sensors


Controller


Sensors

Controller

Actuator

End Effector

Body


Robot Body is typically defined by links and
joints


A link is a part, a shape with physical
properties.



A joint is a constraint on the spatial relations
of two or more links.




Robot Body

Types of Joints


Revolute, Cylindric, Prismatic, Screw, Spherical

10/19/2013

UF Flight Controls Lab

5

a
3
4

a
45
,
a
56

Mitsubishi PA10
-
6C


End Effectors


The Component usually attached at the
end of the robotic arm to accomplish the desired task


Examples : Hand, torch, wheels, weld gun

Robot End Effectors

End Effector


Actuators: ‘Muscles’ of the robot


These can be electric motors, hydraulic
systems, pneumatic systems, or any other
system that can apply forces to the system.


Robot Actuators


Allow for perception.


Sensors can be active or passive:


Active


derive information from
environment’s reaction to
robot’s

actions, e.g. range sensors.


Passive



observers only, e.g.
temperature sensors, strain
gauge .

Robot Sensors

Range Sensor

Oxygen Sensor

Robot Controller

10/19/2013

UF Flight Controls Lab

9


Controllers direct a robot how to move.


There are two controller paradigms


Open
-
loop controllers execute robot movement
without feedback.


Closed
-
loop controllers




execute robot movement

and judge progress with

sensors. They can thus

compensate for errors.


Kinematics is the study of motion
without regard for the forces that cause
it.


Refers to all time
-
based and
geometrical properties of motion.


Ignores concepts such as torque, force,
mass, energy, and inertia.


Forward Kinematics


Determination of
the configuration, given the starting
configuration of the mechanism and
joint angles.


Inverse Kinematics
-

Determination of
the joint angles, given the desired
position of the end effector.



Robot Kinematics

Machine Vision Basic Theory


Vision


A powerful sense


Models the human eye


Applications


Autonomous vehicles, face
recognition, industrial inspection, safety systems,
Visual stock control etc


No ‘universal’ solution


10/19/2013

UF Flight Controls Lab

11

A Typical machine vision system

Basic Concepts

10/19/2013

UF Flight Controls Lab

12


Characteristics of an image


Composed of pixels


Primary colors


red, green and blue


Segmentation


Partitioning of the digital image
into two or more regions


Edge Detection


Corner Detection


Corners can be used as Feature points





Robotic Harvesting

10/19/2013

UF Flight Controls Lab

14

Robot Harvesting Video

Basic Theory Image Processing


Basic Image information


focal length, line of sight, field of view, intensity of pixel


Projection of point in 3D space onto 2D image plane

10/19/2013

UF Flight Controls Lab

15

Basic Image Processing


Goal: Define Coordinates in 3D Space


Methods:


Motion Capture


Photogrammetry: Your digital camera


Stereophotogrammetry/Videogrammetry


Digital Image Correlation


Projector + IR sensor


Some analysis tools:


Photoshop
(Better, not free),
Gimp

(open source)


Matlab Image Processing Toolbox

(
Digitize07
-
open source)


Microsoft Photosynth Live Labs


Johnny Chung’s Wii Remote Project

(open source)

10/19/2013

UF Flight Controls Lab

16

Flight Control


Basic Process


Extract Feature Points (from intensity spikes in image)


Estimate optic flow vectors


Create estimates of roll, pitch, yaw from average optic flow
vectors , use to formulate control model


10/19/2013

UF Flight Controls Lab

17

Digital Image Correlation

10/19/2013

UF Flight Controls Lab

18

Power Supply

Calibrated Voltage

to Flapping Frequency

High Speed DIC Cameras

Phantom v7 CMOS

0
-
1000 fps

3 halogen lights

VICSNAP, VIC3D Software

Electromagnetic Shaker

Used for excitation while

performing DIC

Wings and Mechanism

Stinger extends from

shaker through load

cell to 18 g mechanism

Mechanism: 1
-
20 Hz

Spray Paint Speckle Pattern

DIC uses temporal tracking
of unique regions of speckles

Vibration isolation

Optical lab table and foam

under shaker

Activity


Think of an application where a robot could help


Make a “design sketch” including:


Task Description (think basic task!)


Basic Actuation Method


Sensors required


Share with neighbor and get feedback on how
might improve design



10/19/2013

UF Flight Controls Lab

19