Post on 14-Dec-2015
ROLLERBLADE BRAKING SYSTEM
Design Team #11
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Design Team #11
Team Members:
Sean Milley
Jamie Zwicker
Jeffrey Aucoin
Dima Eshtaya
Team Supervisor:
Dr. Robert Bauer
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Presentation Overview
Introduction Existing Design Design Requirements Selected Design and Manufacturing Engineering Calculations Budget Testing Further Recommendations Conclusion Questions
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Introduction4
Existing Design Proposed Design
http://www.jacqdesign.com/img/blog/photos/RollerbladeCrossfire4D.jpg
Areas of Improvement
Balance and Stability
Difficulty/Technique
Pad Wear and Lifetime
Stopping Distancehttp://www.skatescool.com/inline-skating/learn-how-to-t-stop-on-inline-skates/
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Requirements of Proposed Design
Design Requirements6
Design Requirements
1. Removable
2. Support a 225lb user
3. Improved braking distance
4. Maintain mobility/stability
5. Increased lifetime
6. Serviceable
7. Weather Resistant
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Foot SupportWheel Frame and AssemblyBrake Actuator and ApplicationControl Unit
Selected Design8
Foot Support
Ability to attach over existing footwear
Modified existing snowboard binding
Added third strap
Added additional padding and support
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Wheel Frame
Housing for all components of the skate
⅛” Aluminum welded to form channel
Dimensioned to incorporate range of shoe sizes
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Wheel Assembly
Axles
All rotating pieces
Bearings
Wheels
Brake rotors
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Brake ApplicationBrake Actuator
Braking Unit12
Brake Application
Two Avid Juicy III hydraulic calipers
One actuating piston
Two custom made stainless steel disc brake rotors
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Brake Actuator14
DC Electric Motor
Planetary Gear
Box
Power Screw
Slider Nut
Hydraulic Piston
Piston Plunger
Handheld ControllerSkate Circuit
Control Unit15
Handheld Controller
Controls braking force
Wireless Adapted slot car
remote Added rapid
prototyped box Inserted solid
state circuitry
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Handheld Circuit17
Skate Unit
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
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Skate Circuit19
Arduino Microprocessor20
Reads in PWM from XBee Converts to percent
Reads in analog feedback from Force Sensor Converts to percent
Calculates error Implements Digital PID
Control Sends Motor Controller
commands speed and direction
http://blog.makezine.com/arduino_duemilanove_redo.jpg
Brake Force CalculationsMotor and Power Screw Torque CalculationsHydraulics Calculations
Engineering Calculations21
Brake Torque Calculations22
Disk Brake Calculations23
Power Screw Calculations
Power Screw Specs
Output Force
Output rpm
Output Rev/s
Torque N*m
Torque in*lb
Thread Type
444 7.41.45
412.8
69¼-20
LH
Force Lb
Force N
161.9
720.1
http://www.roton.com/application_engineering.aspx
Required Actuating Force = 78.5N
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Hydraulic Calculations
One piston For two Calipers
Piston Displaces 1.75ml for a 1” stroke
Maximum Allowable Clearance = 1.4mm
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Initial BudgetFinal Cost
Budget26
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Initial Budget1 Braking, 1 Non-braking
Description Qty Unit Price Total Price
Totals
Roller Blade Prototype 1 $100.00 $100.00 Attachment screws and bolts 1 $20.00 $20.00 ratchet straps 6 $9.99 $59.94 strap buckle 6 $12.99 $77.94 axle rod 1 $6.50 $6.50
square channel 1 $20.00 $20.00 plastic foot support 2 $45.00 $90.00
8 x 90mm wheels with bearings 1 $79.99 $79.99 Section Sub-Total $454.37Braking Planetary gear and power screw motor 1 $35.55 $35.55 Rotor 2 $10.00 $20.00 Hydraulic brake caliper with lever controlled piston 1 $150.00 $150.00 Hydraulic brake caliper 1 $80.00 $80.00 Hydraulic fluid 1 $20.00 $20.00 Section Sub-Total $305.55Wireless Controller Transmitter 1 $40.00 $40.00 Receiver 1 $40.00 $40.00 Micro Controller 1 $108.00 $108.00 Motor Controller 1 $50.00 $50.00 Section Sub-Total $238.00Safety Equipment Helmet 1 $29.99 $29.99 Mouth guard 1 $10.00 $10.00 Section Sub-Total $39.99Power source battery pack and charger for actuator motor 1 $23.99 $23.99 16 AA batteries for wireless controller 1 $20.00 $20.00 Section Sub-Total $43.99Total Summary sub total $1,081.90 13% tax $140.65 10% miscellaneous $108.19
final total
$1,330.74
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Final Cost Description Qty Unit Price Total Price TotalsRollerblade Wheels 1 $50.84 $50.84 Wheel Frame, Axel Rod, Steel and Aluminum 1 $58.76 $58.76 Bolts and Fasteners 1 $8.77 $8.77 5/16" Snap Rings 1 $12.20 $12.20 Electronics Isolator Pad 1 $9.61 $9.61 Acetone 1 $7.79 $7.79 Section Sub-Total $147.97Braking Planetary Gear Motor W/RS-370 1 $50.31 $50.31 Motor 2 (Brushless) 1 $24.84 $24.84 Motor 3 1 $67.77 $67.77 Motor 4 1 $7.90 $7.90 Avid Juicy 3 Hydraulic Brake Caliper Kit 2 $96.05 $192.10 3/16" Hydraulic T-Fitting 1 $7.16 $7.16 Hydraulic fluid 1 $7.90 $7.90 Section Sub-Total $357.98Wireless Controller SFE Maxstream 1mW XBEE Transciever w/ SFE XBee Explorer
Regulated Base2 $43.61
$87.22 Arduino Duemilanove USB Microcontroller 1 $37.06 $37.06 Pololu High Power Motor Controller 9A 1 $122.31 $122.31 Miscellaneous Electrical Components 1 $143.56 $143.56 Variable Resistors 3 $8.28 $24.84 Force Sensor 1 $130.05 $130.05 Hand Controller Frame 1 $47.22 $47.22 Section Sub-Total $592.26Power Sources 9V Batteries 12 $3.81 $45.75 7.2V Battery Pack w/ Charger 1 $22.59 $22.59 Section Sub-Total $68.34Foot Support Snowboard Bindings 1 $55.37 $55.37 Ratchet Straps and Buckles 1 $13.57 $13.57 Boot Wrapping 1 $39.55 $39.55 Leg Padding 1 $6.59 $6.59 Section Sub-Total $115.08
Total Summary Grand Total $1,281.63
Final Cost
Slider Nut TestingForce Sensor TestingPID TuningInitial and Final Brake Testing
Testing29
Slider Nut Tests
Nylon nut striped at 2.48Nm Motor Torque =
1.45Nm Original nut
stripped during application
Inserted brass threads in nut to rectify the issue
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Force Sensor Tests and Calibration Made testing
apparatus Loaded force sensor
No load 20lb 70lb 120lb
Tested Resistance
(Multimeter) Voltage Output
(Oscilloscope) Tuned circuit
Maximum Motor Output = Maximum Sensor Output
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PID Tuning
Tuned mainly by Trial and Error
Tuned to: Maximize
Speed Response Time
Minimize Steady-State Error Oscillations Transient Error
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Braking Test33
10 m 13 m
10 m in 1.8 sec = 20km/hr Original Stopping Distance
Stopping Distance Tests34
Weighted (225lb) User Tests
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Initial Testing
Maximum speed: 30km/h
Average stopping distance from 20km/h: 13m
Stopping Distances from 20km/h Jamie Dima Jeff SeanTrial #1 13.2m 14.6m 14.5m 12.6mTrial #2 13.1m 13.9m 13.6m 12.9mTrial #3 12.5m 12.9m 13.5m 12.6mTrial #4 12.2m 13.3m 12.5m 12.5m
Average 12.8m 13.7m 13.5m 12.7mAverage Group Stopping Distance
13.2m
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Final Testing
Stopping Distances from 20km/h Jamie Dima Jeff SeanTrial #1 10.2m 10.6m 9.8m 9.8mTrial #2 8.7m 10.9m 8.3m 7.8mTrial #3 8.4m 10.5m 11.2m 8.4mTrial #4 6.7m 9.3m 7.5m 7.1m
Average 8.5m 10.3m 9.2m 8.3mAverage Group Stopping Distance 9.1m
Average stopping distance from 20km/h: 9.1m
Improved braking distance by 4.1m
Maximum speed: 27km/h
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Requirements Met
1. Removable
2. Support a 225lb user
3. Improved braking distance
4. Maintain mobility/stability
5. Increased lifetime
6. Serviceable
7. Weather Resistant
1. Snowboard Binding
2. Weight Test
3. Braking Test
4. Wireless
5. Mountain Bike Brake Pads
6. Bolts and Snap Rings
7. Calking and Plexi-Glass
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Requirement How it was met
Areas for Future Improvement
Further Recommendations39
Further Recommendations40
Brushless DC Motor Faster Motor Smaller Brake Calipers
How It WorksFinal Product
Conclusion41
How It Works
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)
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How It Works (Continued)
Arduino reads in XBee signal and force sensor feedback 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 (0-5V)
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Final Product44
Shell CanadaCyclesmithThe BinnacleDr. Robert BauerDr. Ken WilkieJonathan MacDonaldAlbert MurphyAngus McPhersonMark MacDonald
Special Thanks To:45
Questions?46