Transcript Rollerblade Braking System

1
ROLLERBLADE BRAKING
SYSTEM
Design Team #11
Design Team #11
2


Team Members:

Sean Milley

Jamie Zwicker

Jeffrey Aucoin

Dima Eshtaya
Team Supervisor:

Dr. Robert Bauer
Presentation Overview
3
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
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Introduction
Existing Design
Design Requirements
Selected Design and Manufacturing
Engineering Calculations
Budget
Testing
Further Recommendations
Conclusion
Questions
Introduction
4
Existing Design
http://www.jacqdesign.com/img/blog/photos/RollerbladeCrossfire4D.jpg
Proposed Design
Areas of Improvement
5

Balance and Stability

Difficulty/Technique


http://www.skatescool.com/inline-skating/learn-how-to-t-stop-oninline-skates/
Pad Wear and
Lifetime
Stopping Distance
6
Design Requirements
Requirements of Proposed Design
Design Requirements
7
1.
Removable
2.
Support a 225lb user
3.
Improved braking distance
4.
Maintain mobility/stability
5.
Increased lifetime
6.
Serviceable
7.
Weather Resistant
8
Selected Design
Foot Support
Wheel Frame and Assembly
Brake Actuator and Application
Control Unit
Foot Support
9


Ability to attach over
existing footwear
Modified existing
snowboard binding
 Added
 Added
third strap
additional
padding and support
Wheel Frame
10
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Housing for all
components of the
skate
⅛” Aluminum welded
to form channel
Dimensioned to
incorporate range of
shoe sizes
Wheel Assembly
11
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Axles

All rotating pieces
 Bearings
 Wheels
 Brake
rotors
12
Braking Unit
Brake Application
Brake Actuator
Brake Application
13
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
Two Avid Juicy III
hydraulic calipers
One actuating piston
Two custom made
stainless steel disc
brake rotors
Brake Actuator
14

DC Electric Motor
 Planetary

Power Screw
 Slider

Gear Box
Nut
Hydraulic Piston
 Piston
Plunger
15
Control Unit
Handheld Controller
Skate Circuit
Handheld Controller
16
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

Controls braking force
Wireless
Adapted slot car
remote
 Added
rapid
prototyped box
 Inserted solid state
circuitry
Handheld Circuit
17
Skate Unit
18
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Receives remote input


XBee Transceiver
Acts as PID controller
Arduino Duemilanov
Microprocessor
 Force sensor feedback


Controls motor
Pololu High Power Motor
Controller
 Speed and Direction


Generates brake force

Motor pushing piston
Skate Circuit
19
Arduino Microprocessor
20
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Reads in PWM from XBee
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
Reads in analog feedback
from Force Sensor
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http://blog.makezine.com/arduino_duemilanove_redo.jpg
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Converts to percent
Converts to percent
Calculates error
Implements Digital PID
Control
Sends Motor Controller
commands

speed and direction
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Engineering Calculations
Brake Force Calculations
Motor and Power Screw Torque Calculations
Hydraulics Calculations
Brake Torque Calculations
22
Disk Brake Calculations
23
Power Screw Calculations
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Power Screw Specs
Output
rpm
444
Output
Rev/s
Torque
N*m
Torque
in*lb
Thread
Type
12.86 ¼-20
7.4 1.454
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LH
http://www.roton.com/application_engineering.aspx
Output Force
Force
Lb
Force N
161.9 720.1
Required Actuating Force = 78.5N
Hydraulic Calculations
25
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One piston For two
Calipers
Piston Displaces
1.75ml for a 1” stroke
Maximum Allowable
Clearance = 1.4mm
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Budget
Initial Budget
Final Cost
Initial Budget
1 Braking, 1 Non-braking
Description
Roller Blade
Section Sub-Total
Braking
Section Sub-Total
Wireless Controller
Section Sub-Total
Safety Equipment
Section Sub-Total
Power source
Section Sub-Total
Total Summary
27
Qty
Unit Price
Total Price
Prototype
Attachment screws and bolts
ratchet straps
strap buckle
axle rod
square channel
plastic foot support
8 x 90mm wheels with bearings
1
1
6
6
1
1
2
1
$100.00
$20.00
$9.99
$12.99
$6.50
$20.00
$45.00
$79.99
$100.00
$20.00
$59.94
$77.94
$6.50
$20.00
$90.00
$79.99
Planetary gear and power screw motor
Rotor
Hydraulic brake caliper with lever controlled piston
Hydraulic brake caliper
Hydraulic fluid
1
2
1
1
1
$35.55
$10.00
$150.00
$80.00
$20.00
$35.55
$20.00
$150.00
$80.00
$20.00
Totals
$454.37
$305.55
Transmitter
Receiver
Micro Controller
Motor Controller
1
1
1
1
$40.00
$40.00
$108.00
$50.00
$40.00
$40.00
$108.00
$50.00
$238.00
Helmet
Mouth guard
1
1
$29.99
$10.00
$29.99
$10.00
battery pack and charger for actuator motor
16 AA batteries for wireless controller
1
1
$23.99
$20.00
$23.99
$20.00
$39.99
sub total
13% tax
10% miscellaneous
final total
$43.99
$1,081.90
$140.65
$108.19
$1,330.74
Final Cost
Rollerblade
Section Sub-Total
Braking
Section Sub-Total
Wireless Controller
Section Sub-Total
Power Sources
Section Sub-Total
Foot Support
Description
Wheels
Wheel Frame, Axel Rod, Steel and Aluminum
Bolts and Fasteners
5/16" Snap Rings
Electronics Isolator Pad
Acetone
Total Summary
Qty
Unit Price
Total Price
Totals
$50.84
1
$50.84
$58.76
1
$58.76
$8.77
1
$8.77
$12.20
1
$12.20
$9.61
1
$9.61
$7.79
1
$7.79
$147.97
Planetary Gear Motor W/RS-370
Motor 2 (Brushless)
Motor 3
Motor 4
Avid Juicy 3 Hydraulic Brake Caliper Kit
3/16" Hydraulic T-Fitting
Hydraulic fluid
1
1
1
1
2
1
1
$50.31
$24.84
$67.77
$7.90
$96.05
$7.16
$7.90
SFE Maxstream 1mW XBEE Transciever w/ SFE XBee Explorer
Regulated Base
Arduino Duemilanove USB Microcontroller
Pololu High Power Motor Controller 9A
Miscellaneous Electrical Components
Variable Resistors
Force Sensor
Hand Controller Frame
2
$43.61
$50.31
$24.84
$67.77
$7.90
$192.10
$7.16
$7.90
$357.98
1
1
1
3
1
1
$37.06
$122.31
$143.56
$8.28
$130.05
$47.22
$87.22
$37.06
$122.31
$143.56
$24.84
$130.05
$47.22
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1
$3.81
$22.59
$45.75
$22.59
$592.26
9V Batteries
7.2V Battery Pack w/ Charger
$68.34
Snowboard Bindings
Ratchet Straps and Buckles
Boot Wrapping
Leg Padding
1
1
1
1
$55.37
$13.57
$39.55
$6.59
$55.37
$13.57
$39.55
$6.59
$115.08
Section Sub-Total
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Final Cost
Grand Total
$1,281.63
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Testing
Slider Nut Testing
Force Sensor Testing
PID Tuning
Initial and Final Brake Testing
Slider Nut Tests
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Nylon nut striped at
2.48Nm
 Motor
Torque =
1.45Nm
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Original nut stripped
during application
Inserted brass threads
in nut to rectify the
issue
Force Sensor Tests and Calibration
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Made testing apparatus
Loaded force sensor
No load
 20lb
 70lb
 120lb
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Tested
Resistance (Multimeter)
 Voltage Output
(Oscilloscope)
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Tuned circuit
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Maximum Motor Output
= Maximum Sensor
Output
PID Tuning
32
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Tuned mainly by Trial
and Error
Tuned to:
 Maximize
 Speed
 Response
Time
 Minimize
 Steady-State
Error
 Oscillations
 Transient
Error
Braking Test
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10 m
10 m in 1.8 sec = 20km/hr
13 m
Original Stopping Distance
Stopping Distance Tests
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Weighted (225lb) User Tests
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Initial Testing
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Maximum speed:
30km/h
Average stopping
distance from 20km/h:
13m
Stopping Distances from 20km/h
Jamie
Dima
Jeff
Sean
Trial #1
13.2m
14.6m
14.5m
12.6m
Trial #2
13.1m
13.9m
13.6m
12.9m
Trial #3
12.5m
12.9m
13.5m
12.6m
Trial #4
12.2m
13.3m
12.5m
12.5m
Average
12.8m 13.7m 13.5m 12.7m
Average Group Stopping
Distance
13.2m
Final Testing
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Stopping Distances from 20km/h

Jamie
Dima
Jeff
Sean
Trial #1
10.2m
10.6m
9.8m
9.8m
Trial #2
8.7m
10.9m
8.3m
7.8m
Trial #3
8.4m
10.5m
11.2m
8.4m
Trial #4
6.7m
9.3m
7.5m
7.1m
8.5m
10.3m
9.2m
8.3m
Average
Average Group Stopping
Distance
9.1m
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Average stopping
distance from 20km/h:
9.1m
Improved braking
distance by 4.1m
Maximum speed:
27km/h
Requirements Met
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Requirement
How it was met
1.
Removable
1.
Snowboard Binding
2.
Support a 225lb user
2.
Weight Test
3.
Improved braking distance
3.
Braking Test
4.
Maintain mobility/stability
4.
Wireless
5.
Increased lifetime
5.
Mountain Bike Brake Pads
6.
Serviceable
6.
Bolts and Snap Rings
7.
Weather Resistant
7.
Calking and Plexi-Glass
39
Further Recommendations
Areas for Future Improvement
Further Recommendations
40
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Brushless DC Motor
Faster Motor
Smaller Brake Calipers
41
Conclusion
How It Works
Final Product
How It Works
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
User pushes down on
handheld remote
 Varying
the voltage to
the XBee (0-3.3V)
 XBee sends wireless
signal

XBee receives signal in
skate
 Outputs
PWM (0-3.3V)
How It Works (Continued)
43

Arduino reads in XBee signal
and force sensor feedback
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Coverts both to a percentage
Determines error
Implements digital PID control
Sends signal to the motor
controller (4 Byte string)
Motor Controller receives
data string


Operates motor
Force sensor feedbacks
analog voltage to Arduino (05V)
Final Product
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Special Thanks To:
Shell Canada
Cyclesmith
The Binnacle
Dr. Robert Bauer
Dr. Ken Wilkie
Jonathan MacDonald
Albert Murphy
Angus McPherson
Mark MacDonald
Questions?
46