Motion Tracking &
Position Acquisition
Final Design Review
Solomon Gates | William K. Grefe | Jay Michael Heidbreder | Jeremy Kolpak
Overview of Project Objective
Achieve accurate and precise motion of laser
pointer directed at a locator beacon
Obtain precise object position from sensor input
Design Objectives
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Simulate control system
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Final component decision
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Refine motor control system
Test tracking accuracy
Maintain motor feasibility
Final motor justification
Pulley gear ratio
Sensor specifications
Cost analysis
Completed simulation and design specs on
schedule
Plan of Action
This week
Linear Simulation
Non-Linear Simulation
Week 8
Parts Purchasing
Week 10
Assemble & Test Pan/Tilt
Week 11
Simulate Position Acquisition
Test Beacon and Receivers
Week 12
System Integration
Week 13
Final Testing
Original Design Specifications
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Object tracking velocity:
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Distance to object: ½ft – 20ft
Range of motion:
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Pan range of 180°
Tilt range of 90°
Sensor accuracy:
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Object velocity of 10 mph
Pan/Tilt velocity of 10 radians per second
Object acquisition within 1 second
Detection distance of ½ft – 20ft
Detection cone 60° – 180°
Beacon accuracy:
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Transmission distance of up to 20ft
Transmit 30 times per second
Testing Procedure
Fixed point accuracy & acquisition speed
Sinusoidal input tracking
Realistic tracking (torque saturation)
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Trapezoidal input tracking
Random path tracking
Tolerance Analysis
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Fixed point accuracy:
Sinusoidal tracking accuracy:
Random path tracking accuracy:
 1/2” @ 20 ft; 1/8” @ 6”
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Beacon acquisition accuracy: unknown
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Tracking moving beacon:
 1” @ 20 ft;  1/4” @ 6”
Part Justification
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Motor candidates:
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GM8274S010, GM8274S013, GM8712-11
Speed and torque requirements met using a
variety of gains and gear ratios connected to
motor candidates
In simulations, large gear ratios gave more
power at slower speeds and visa versa
After different configurations, we arrived at
particular gains and a gear ratio of 4:1
Pulley dimensions were chosen at this ratio
Grooves on pulleys also match ratio
Motor Analysis
Motor Analysis
Motor Analysis
3
13
Motor Analysis
Realistic Tracking Simulation
Realistic Tracking Simulation
Realistic Tracking Simulation
Realistic Tracking Simulation
Realistic Tracking Simulation
Random Path Tracking
Testing Results
Desired
Specifications
Simulation
Results
Θ1
Simulation
Results
Θ2
Tracking
velocity
≥10 rad/sec
12 rad/sec
15 rad/sec
Acquisition
time (over
π radians)
≤1.5 seconds
0.8 seconds
0.6 seconds
Linearization Model
Sensor Design: Beacon
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Ultrasonic transceiver
sends sound wave in a
60° cone
Distances of up to 30ft
RF signal transmitted
in 360°
RF signal range of up
to 300ft
Sensor Design
Beacon will be built from six ultrasonic transceivers
to allow 360° range
Three receivers will detect signal propagation time
Final Part Decision
Supplier: Pittman Express
Lo-Cog DC Gearmotor GM8724S010 (qty: 2)
Supplier: Stock Drive Products/Sterling Instrument
100 Teeth, Aluminum Alloy Timing Pulley -- A 6A61-00NF03112 (qty: 2)
25 Teeth, Aluminum Alloy Timing Pulley -- A 6A 6-25DF03106 (qty: 2)
Supplier: Oatley Electronics
40KHz transmit transducer -- MA40A3S (qty: 6)
40KHz receive transducer -- MA40A3R (qty: 3)
Supplier: Abacom Technologies
RF transmitter -- AM-TX1-4xx (qty: 1)
RF receiver -- AM-HRR3-xxx (qty: 3)
Cost Analysis
Item
Motors
Large pulleys
Small pulleys
Belts
Laser Pointer
RF Transmitter
Ultrasonic Beacon
RF Receiver
Ultrasonic Receiver
Micro Controller
Miscellaneous Electronics
Quantity Cost (each) Total Cost
2
$112.00
$224.00
2
$11.87
$23.74
2
$13.01
$26.02
2
$1.50
$3.00
1
$3.00
$3.00
1
$12.61
$12.61
6
$3.00
$18.00
3
$10.95
$32.85
3
$3.00
$9.00
3
$20.00
$60.00
1
$50.00
$50.00
Total Cost
$462.22
Schedule