Download Swish Sleeve Design Constraint Analysis

Swish Sleeve
Design Constraint
Analysis
Team 7: Stephen MacNeil, Michael Kobit,
Sriharsh Achukola, Augustus Hong
Project Overview
We would like to design and implement a shooting
sleeve made from compression material that
basketball players or pitchers could wear to track
their motion, without the use of cameras. This
prevents current occlusion issues inherent in
optical motion capture. The sleeve can be
extended to other sports as well and beyond the
scope of this class could be extended to an entire
suit which could monitor sports performance in
athletes.
PSSCs
1. Package and send sensor data wirelessly using XBee
2. Capture rotational and translational motion for each joint
3. Coordinate movement between each joint so that the motion
of an arm can be recreated
4. Using OpenGL on an atom board, render the motion captured
by the sensors
5. Kalman filter the sensor results so that variances and noise
are ignored
Major Design Constraint
•Real-time motion capture and accurate sensor
readings.
•Sleeve must be flexible, light and not impair movements
•Low power consumption to improve battery life, at least
the duration of a full game
•Transmit/Receive data packets (the 3 IMU readings) at
a fast rate for image rendering
•Appropriately translate readings and display on screen
Computation
Requirements
• Transmitter sleeve
◦ Calculate wireless signal strength
◦ Take samples and transmit data
• Base station
◦ Kalman filter packet data from transmitter sleeve
◦ Trigonometric functions to determine position
◦ OpenGL to output 3D image to screen
Interface Requirements
Microcontroller(on sleeve):
Talk to XBee
Talk to the 3 IMUs
Show Status bits and possibly battery information on
LCD
Atom Board(base station)
Display sensor data on monitor through a DVI cable
Talk to XBee
On Chip Peripheral
Requirements
1 I2C port for the 3 IMUs
1 SPI port for LCD
1 SCI port for XBee
2 timers for measuring sampling intervals
4 General I/O Pins for pushbuttons
Off Chip Peripheral
Requirements
XBee module for communication between
microcontroller and Atom board
Shift registers for LCD
Power Supply Components
Block Diagram
Power Constraints
Packaging Constraints
• Swish Sleeve
◦ Small enough to wear
◦ Can not be cumbersome
◦ Flexible wiring
◦ Easy to take off/put on
• Base station
◦ Compact and self-standing
◦ Mobile
Cost Constraint
•Swish Sleeve
•Total Price: ~$500
•Includes 3 sensor modules
•Image rendering base station
•Competition: MotionNode
•Price: $500 + $1000 per sensor module
Micro-Controller
(ATxmega128A1)
• Operating supply voltage (typically)
◦ 1.8/2.5/3.3V
• Max. supply current @ 32 MHz
◦ 200 mA
• 128 KB Flash + 8 KB SRAM
• Peripherals:SCI, SPI, TIM, UART, PWM, A/D and I2C/SMB
• Special Features:
◦ Power-on Reset & Programmable Brown-out Detection
◦ Internal and external Clock options
◦ 4 Sleep Modes: Idle, Power-down, Power-save and extended standby.
◦ Advanced Programming, Test and Debugging Interfaces
■ JTAG
■ PDI
Wireless Module
(XBee Series 1)
XBee 1mW Chip Antenna - Series 1
low power 1mW output
300ft (100m) range
Long enough for our considerations
250 kbps max data rate
Easy to set up
IMU
(SEN-1021)
• 6 DOF
◦ 3-axis accelerometer
◦ 3-axis gyroscope
• Small size (.6" x .65")
• Pre-packaged board with sensors oriented in
the same direction
• Output is I2C
• Low power
• Best price for 6 DOF
Power Supply
(Tenergy Lithium-Ion 18650 Battery)
• Performance
◦ Voltage: 3.7 Volts
◦ Current: 4400 mAh
• Built-in PCB protection from surges and spikes
• Voltage Regulation
◦ Regulated down to 3.3 Volts
◦ Linearly regulated using LM117
◦ Capable of delivering 2A after being regulated.
• System runs at approximately 350 mW (276mW ideal)
Atom board
(Intel Atom N270)
• 1.60 GHz
• Main component of base station
• Heavy calculations
◦ Kalman filtering
◦ Trigonometric functions
• Create 3D image of motion
Questions?