Utah State University

deadmancrossingraceAI and Robotics

Nov 13, 2013 (3 years and 6 months ago)

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Steve Gunderson

chapodecalifornia@hotmail.com

(916) 662
-
4244

Utah
State University

March 11
,
2010

Acknowledgements


Dr.
YangQuan

Chen
: Research background and
technical instruction

Agenda


Overview


Impact of engineering


Principle of operation


Types


Implementation


Application


Major specifications


Limitations


Purchasing


References

Typical Stepper Motor

http://en.wikipedia.org/wiki/Stepper_motor

Overview


Stepper motors are brushless electric
motors that operate through a radial array
of steps


The step sizes vary from motor to motor
and can be used in control applications
where a defined resolution is helpful with
motor manipulation


Overview


Stepper motors have become widely
implemented in many ways due to their
controllability without any form of feedback
loop


Even without feedback, a stepper motor
may be controlled to a good degree of
precision

Impact of Engineering


The functionality of stepper motors has
been so widely accepted that they have
revolutionized the usefulness and ease of
implementation of electric motors


They can be used in stable and reliable
control system that function with great
precision and accuracy

Principle of Operation


Voltage applied to
the motor causes
the rotor to
incrementally spin


More voltage causes
more increments to
be bypassed around
the circle


Typical Stepper Motor

http://en.wikipedia.org/wiki/Stepper_motor

Types


Permanent Magnet stepper motors
maintain a permanent magnet within the
housing


Variable Reluctance stepper motors with
iron rotors have rotor points attracted to
stator magnet poles


Hybrid Synchronous stepper motors are the
combination of the previous two for better
performance

Implementation


Stepper motor control
varies almost as widely as
the stepper motors
themselves


Control implementation is
heavily dependent upon
internal configuration and
application needs

Stepper Motor Control

http://www.tigoe.net/pcomp/code/category/ardu
inowiring/51

Implementation


Drive circuitry for bi
-
polar
stepper motors can be
complicated but may be
worth the additional
torque that the actuator
would be able to provide
once configured properly

Stepper Motor Control

http://www.tigoe.net/pcomp/code/category/ardu
inowiring/51

Implementation


Half
-
stepping and micro
-
stepping are two
implementation modes
where the angular
resolution may be
increased with little
change to the control
circuitry

Stepper Motor Control

http://www.tigoe.net/pcomp/code/category/ardu
inowiring/51

Application


Countless types of stepper motor
configurations are in use today all
throughout the world


A wide variety of markets can take
advantage of them for precise control
actuation

Application


Smaller high precision
stepper motors are often
used for common
actuation tasks


Their small enclosures
are easy to mount to
hardware and at low
speeds can provide high
torque

Stepper Motors

http://news.thomasnet.com/IMT/archives/2006/
07/scavenge_materials_to_build_tinker_your_o
wn_cnc_machine.html

Application


Robotic systems can take
advantage of a stepper
motor’s quick response
and high precision
without the constant need
of a feedback loop


Where needed they can
also interface with belts
and drive trains

Stepper Motor

http://www.designworldonline.com/uploads/Ima
geGallery/G4.Handler.stepper.motor.gif

Major Specifications


Motors tend to vary widely in response and
must be characterized in order to properly
control and implement them in a design


Stepper motor characteristic equations are
a good start to understanding their
behavior, as long as the control circuitry is
also taken into account

Limitations


Stepper motor resolution is completely
dependent upon the number of teeth on
the rotor


As motor velocity increases, there is also a
marked decrease in the total torque output
which can comprise certain
implementations of the actuator

Limitations


Different tooth constructions in the motors
can lead to varied efficiencies and
controllability


More complicated motor designs also may
require more complicated control
electronics with amplifiers and many input
lines

Purchasing


Stepper motors may be readily purchased
from many online retailers


Small electronic stepper motors are found
at digikey.com or mouser.com


Large
-
application stepper motors may be
obtained from specialty manufacturers and
retailers

References


Wikipedia.org



Mechatronics



An Integrated Approach” by
Clarence W. de Silva

Questions?