West Texas BEST Robot Project

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West Texas BEST Robot Project
EE3332 - Group 2
Kevin Springer Ahmed Saheb Corby White Daniel Akst
Advisor Dr. Parten
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Overview

• Objective
• Game Rules
• Design Constraints
• Final Design
• Maximum Reach
• Wiring
• Torque Calculation
• Movement measurements
• Strategy for game
• Modifications
• Torque Calculations
• Various Performance Calculations
• Daughterboard
• Budget
• Gantt Chart
• Resources

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Project Objective

• Our objective is to design and build a robotic
  arm that can compete in the West Texas BEST
  competition.

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Game Rules
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Game Rules, Contd
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Design Constraints

• Maximum Weight 24 lbs.
• Must fit within 24 cube at beginning of
  competition
• Can only be constructed using approved parts
• Must be compatible with speed controller system,
  and new DSP system

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Final Design
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Pulley Implementation
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Pulley Implementation, Contd
Main Arm
Forearm
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Offset Design
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Offset Design, Contd
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Ball Collector
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Component Weights
Pulley 3 oz. Coffee Can 10 oz. Light Switch 3
oz. Battery 11 oz. Servo 2 oz. Small Motor 6
oz. Large Motor 17 oz. ½ inch pvc pipe 0.2 oz.
per inch of pipe 1 inch pvc pipe 0.4 oz. per inch
of pipe ½ inch pvc elbow 0.5 oz. ½ inch pvc tee 1
oz. 1 inch pvc elbow 2 oz. 1 inch pvc tee 3 oz.
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Main Arm Torque
27.6
48 oz.in.
278 oz.in.
72 oz.in.
30.7 oz.in.
12 oz.in.
68 oz.in.
638 oz.in.
35 oz.in.
Main Arm Motor Globe Motor 455A116-2 (Large
Motor) Lever arm length 10 inches Torque
required 1143 oz.in. Max Torque from motor,
using lever arm and pulley 1536 oz.in.
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Forearm Torque
32.4 oz.in.
6 oz.in.
268 oz.in.
Main Arm Motor Globe Motor 415A157-2 (Small
Motor) Lever arm length 6.5 inches Torque
required 306.4 oz.in. Max Torque from motor,
using lever arm and pulley 440 oz.in.
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Initial Unfold Time
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Ball Collector Time
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Base Rotation Time
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Main Arm Operation Time
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Forearm Operation Time
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Wiring
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Robot Box Connections
Pin 1- Speed Controller
Pin 2- Speed Controller
Pin 4-Servo
Receiver
Power
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4 Motors, 2 Speed Controls
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Calibration with Speed Controllers
Left Control
Right control
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Wiring, Contd
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Robot
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Maximum Reach
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35
43
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Minimum Reach
15
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Connections
12 Max Outputs, Max of 8 at one time
Transmitter
Receiver
4 Inputs
DaughterBoard
DSP
Motors
Servos
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DSP Board

• Industry standard DSP with analog I/O
• VAB software to graphically construct algorithms
• Direct object, flash programming of the DSP
  hardware
• 32 Bit Processor
• Connects to a PC via a USB cable
• Operates on 3.3 Volts
• Supports an optional motor control daughter board
  for robotics

Springer
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Block Diagram
Springer
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H-Bridge Comparison
Springer
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TI TPIC0107B

• Selected H-Bridge for Daughter Board
• Easy to use
• Outputs more than enough current
• Requires no external capacitor for filtering

Springer
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TI TPIC0107B Block Diagram
Springer
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Optocouplers
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NEC PS2053-4

• High Isolation Voltage
• High Current Transfer Ratio
• Requires Low Current Input

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Voltage Regulator MAX1685
Features

• Up to 96 efficiency
• 1A guaranteed output
• 2.7V to 14V input range
• Switching regulator
• Uses Buck Topology
• Large amount of external components

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Buck Topology

• DC to DC conversion
• Primarily used to step down voltage

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Daughter Board Block Diagram
H-Bridge
Motor
DSPJ1 Header
Optocoupler
H-Bridge
Motor
MotorOutput
H-Bridge
Motor
Optocoupler
H-Bridge
Motor
Optocoupler
ServoOutput
4 Servos
Springer
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Daughter Board Budget Parts
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Daughter Board Schematic
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Final Daughter Board Product
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R/C Transmitter

• Encodes 4 signals into 1
• C1 controls the frame period
• C2 controls the rate at which the amplitude
  increases
• X1 Represents the Crystal

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Transmitted Signal

• Tf is the fixed time
• Tv is a variable time
• 1ms corresponds to left/down position
• 1.5ms corresponds to neutral
• 2ms corresponds to right/up position

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RF Receiver
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Programming RIDE Software
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Testing Setup
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DSP PWM Output
2.0 ms
1.5 ms
1.0 ms
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Servo Control Signal

• Verified Power Signal
• Required more time for debugging
• Unsuccessful in driving the servos with the
  daughter board
• Problem most likely from programming

Servo 5 Volt Power Signal
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Budget
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Gantt Chart
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References

• Judy Patterson
• http//www.digikey.com
• http//www.motorola.com
• http//www.hyperception.com
• http//www.ti.com
• http//www.maxim-ic.com
• http//www.mouser.com
• http//www.powerdesigners.com
• http//www.futaba-rc.com
• Fall 2003 Lab 3 Team
• Web CT
• Dr. Parten
• Oludare Sami

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Any Questions?