Transcript Proposal_Presentation.ppt

ECE 480 Design Team 6
Lightweight Speed and
Distance Sensor for Skiers
and Snowboarders
Michael Bekkala
Michael Blair
Michael Carpenter
Matthew Guibord
Abhinav Parvataneni
Facilitator: Dr. Shanker Balasubramaniam
Agenda
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Background
Objective
Design Specifications
Potential Solutions
Proposed Solution
Conceptual flowchart and Hardware
Goal of Competitive Sports
1)
2)
3)
Win
Perform better than the competition
Improve performance
• Requires tracking of statistics
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Jump Higher
Run Faster
Hit Harder
Bicycle Speedometer
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Sensor mounts to wheel and frame
Counts time between
wheel sensor passing
frame sensor
Calculates wheel speed
Forward speed is
proportional to rotation of wheel
Nike Plus (Nike+)
Sensor placed in shoe
 Determines how long pressure is
applied to the foot
 The time that pressure is
applied is directly
proportional to the
runner’s speed
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Objective
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Design a speed and distance sensor for skiing
and snowboarding
Current Products:
• Expensive
• Inaccurate
• Inconvenient
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Objective:
• Greater accuracy
• Lower cost
• Improve functionality
Design Specifications
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Safety
• Disable display while moving
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Functionality
• User definable auto shutdown time
• PC interface for data review
• Ease of use in winter apparel
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Packaging
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Operate at subzero temperature (-10°F)
Shock resistant
Waterproof
Weigh less than 2 lbs
Cost - less than $500
Potential Solutions
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Relative Positioning
Inertial Navigation System (INS)
Global Positioning System (GPS)
Integration of INS and GPS
1. Relative Positioning
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Transmitter locally placed
• Sends out signal to receiver
• More transmitters = Better accuracy
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Receiver gets signal from
transmitter
• Calculates distance from
transmitter
• Derivative of distance = Speed
1. Relative Positioning
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Advantages:
• Accurate
• Reliable
• Independent of external systems
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Disadvantages:
• Complex
• Requires a locally placed transmitter
• Relative position vs. absolute position
2. Inertial Navigation System
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3 Accelerometers
• Measure Linear Acceleration
• X, Y, Z Directions
• Integrate to get speed and distance
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3 Gyroscopes
• Measure Angular Velocity
• Pitch, Roll, Yaw
• Integrate to get angular
position
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Coordinate conversion
• Body Frame to ECEF
2. Inertial Navigation System
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Advantages:
• Very accurate for short periods of time
• Updates faster than GPS
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Disadvantages:
• Requires at least 6 sensors
• Susceptible to bias drifts
• Error increases over time (t^2)
• Requires initial condition
3. Global Positioning System
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Receives time data from satellites
• Requires very accurate timing
• Atomic clocks on board satellites
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Triangulates position
• Uses distance from
satellites
• Fourth satellite
used for error
correction
3. Global Positioning System
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Advantages:
• Inexpensive
• Low Power
• Gives absolute position
• Reliable over long periods
of time
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Disadvantages:
• Low accuracy for moving targets
4. Integration of GPS and INS
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Proposed Design
Combines both systems into one
Takes advantage of each system
• Short term accuracy of INS
• Long term reliability of GPS
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GPS keeps INS errors in check
Use Kalman filter to improve
accuracy of integrated system
4. Integration of INS and GPS
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Advantages:
• Most accurate
• Takes advantage of each system
• Gives absolute position
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Disadvantages:
• More complex
• Requires heavy computation
• Requires more hardware
Conceptual Design
Hardware Components
Ardupilot Sensor Board - Six Degrees of Freedom
• Three axis accelerometer (x,y,z)
• One axis gyroscope (roll)
Gyro Breakout Board - LPY5150AL Dual 1500°/s
• Dual axis gyroscope
• Senses pitch and yaw
Hardware Components
Venus GPS with SMA Connector
•Up to 10Hz refresh rate
•28mA operating current
•Accuracy is <2.5m
Quadrifilar V Omnidirectional Passive GPS Antenna
•Passive Antenna
•-5dB Gain