QEF Project Curriculum

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QEF Project - Curriculum
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Module 4Fundamentals of Robot Control
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Module 4 Fundamentals of Robot Control

• Objective
• Introduce different motors
• Raise discussion on simple circuit
• Introduce feedback control and robot control
• Sections
• Lecture
• 4.1 Introduction to Motors
• 4.2 Motors used in Robotics
• 4.3 Motor in a toy car
• 4.4 Introduction to control
• 4.5 Self-learning Resources

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Module 4 Fundamentals of Robot Control

• Sections
• Lab
• 1 Simple circuit
• 2 Introduction to robot motion control

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4.1.1 Introduction to motors
The motors convert electrical energy to
mechanical work as the output shaft turns.
The magnetic force turns the coil and the
shaft. The speed of the motor can be controlled
by changing the supplying voltage.
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4.1.2 Motors used in Robots
DC motors, AC motors, stepping motors and servo
motors are popularly used in robots. Following
are their brief introductions

• DC motors
• Input continuous direct current or voltage
• Output rotation of the motor shaft.

• AC motors
• Input continuous alternating current or voltage
• Output rotation of the motor shaft.

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4.1.2 Motors used in Robots
A stepping motor converts electrical pulses into
specific rotational movements.

• Stepping motors
• Input a pulse train
• Output rotation of the motor shaft.

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4.1.2 Motors used in Robots

• Servo motors
• Input coded signals
• Output a specific angular position.

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4.1.3 Motors in a toy car
DC motors are widely used in toy cars as shown in
the following figure.
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4.1.3 Motors in a toy car
Different motions can be generated by controlling
rotations of the motors.
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4.1.4 Introduction to control

• Here we consider a control problem How to
  maintain the position of the barrel by
  controlling the motor?

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4.1.4 Introduction to control

• Open loop control

In the open loop control, the force generated by
the motor is made equal to the weight of the
barrel all the time.
Diagram of open loop control
This method will fail to achieve the objective if
there are any errors in inflow supply and motor
control.
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4.1.4 Introduction to control

• Close loop control (feedback control)

Feedback - the output of a system is returned to
modify the input
Diagram of feedback control
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4.1.4 Introduction to control

• A water tank with feedback control

When the water reaches the desired level, the
valve will be completed closed.
A water tank with feedback control
Diagram of the control system of the tank
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4.1.5 Self Reading Resources

• http//hyperphysics.phy-astr.gsu.edu/hbase/magneti
  c/motdc.htmlc1
• http//www.sciencejoywagon.com/physicszone/lesson/
  otherpub/wfendt/electricmotor.htm
• http//www.theorem.net/theorem/lewis1.html
• http//en.wikipedia.org/wiki/Control_theory

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