Team Dominate(d?) The Machine

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Team Dominate(d?)
The Machine
Synopsis
 Motorcycles are complex systems, containing many
variables beyond what is displayed by standard
gauges or rider intuition.
 Understanding of these variables becomes more
important in racing situations, where slight changes
can significantly alter outcomes.
 Our goal is to digitally characterize some of these
variables, transmit information to an acquisition
system, and then interpret them in order to improve
motorcycle development and riding techniques.
Defining un-measured variables
 The variables we decided to characterize are:
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Acceleration
Deceleration
Lateral Acceleration
Tire temperature
Lean angle
Suspension travel
Although engine speed and velocity are already measured
by standard gauges, we decided to also transmit these
data values for correlation with the other acquired data.
High-Level Block Diagram
Subsystem specifics: Sensors
 Accelerometer
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LIS3LV02DQ 3 Axis Accelerometer
Cost ~ $40
 Digital Output- SPI or I2C digital interface
 +/- 2g acceleration range
 Small size (21x23mm)
 3V power
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Subsystem specifics: Sensors
 Preferred Accelerometer/Inertial Measurement
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IMU 5
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Cost ~ $110
Combines 3 axis accelerometer and angle sensor (gyros)
Senses Roll and Pitch (Lean angle & wheelie)
Senses Acceleration in X, Y, Z axes
+/- 3g acceleration range
Small size (20x23mm)
Analog Output from IMU
3V Power
Subsystem specifics: Sensors
 Tire Temperature
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Omega OS136
Cost ~ $175 x 2
 Non-contact IR temperature sensing
 Accurate reading range 0o-400o F
 Reads 7 measurements per second
 Analog Output 0-5V
 12V Power
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Subsystem specifics: Sensors
 Suspension Travel
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Sharp IR proximity sensor
Cost ~ $12 x 2
 Measures distance between
fender and fixed mounted
point of sensor
 Analog output
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 3.1V @ 10cm, 0.4V @ 80cm
High-Level Block Diagram
Subsystem specifics: Sensors
 Engine Speed/Velocity/Throttle Position/Gear Indicator
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OEM sensors/data decoders – <$100
Engine Speed/Velocity Sensor Output
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Throttle Sensor Output
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Pulse signal - frequencies proportional to speed
Analog output linear with increasing throttle
Gear Indicator
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A known engine speed and velocity can be used to calculate the current
gear selection
Not accurate while clutch is disengaged
 Only inaccurate during small fractions of time in race situations.
Subsystem Specifics: Sensor
Communication
•Analog to Digital Converter
•Digital signal transmitted over I2C
•Signal received and processed by Data Handling Unit
•Transmit digital signal for superior quality over analog
•Data latches to hold values until next reading from
sensor
Power
 Power will be derived from the 12 volt DC
motorcycle battery
 Centrally located step down converters will
adjust power to 5 and 3 volt supply.
 A power filter and step down converters will
be located on a circuit board near the Data
handler
Subsystem Specifics: Data
Handling
 FPGA Prototype Board
 I2C Data Inputs
 RS232 Output
 Multiplexing ability for sensor selection
 Soft Core processor emulation
High-Level Block Diagram
Subsystem Specifics: Data
Transmission
 RF downlink
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Xbee-Pro wireless modem
RS-232 serial input for downlink communication
 USB interface to computer base station
 2.4 GHz, 115200 bps
 100 mW transmit power
 1 mile range line of sight
 12 channels
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Software
 We will use Visual C++ for the computer
base station
 Advising from Professor John Hauser
(Motorcycle Dynamics Control)
 Verilog code for bus controller and
communication with the data handler
Parts Cost Analysis
 Accelerometer/
Angle Sensor
Tire Temperature
FPGA Board
Suspension Travel
RF Transmission
Speed Sensor
PCB boards
A>D>I2C chip
Total
Domination
$110
$175 x 2
$300
$100
$110 x 2
$20
$33 x 5
$3.50 x 7
$1290
$Priceless
Division of Labor
 Accelerometer /Bank Angle Sensor (Mr. Keogh and Mr. Pearse)
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Acquire data
Transmit I2C
Determine appropriate range for data
 Data Handler (Mr.Olson and Mr. OConnell)
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Read I2C data
Process data
Transmit via RS232
 Software (Mr.Schreiner)
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Read data from USB input
Convert data to standard units
Display data on computer
Risks
 Extreme temperature from exhaust and
engine
 Engine and road vibration
 Physical damage from debris and crash
 Intricate Dynamics of motion too complex
for sensors or analysis
Contingency Plans
 Limit number of sensors for time
 Spare budget for damaged part replacement
 Dynamics analysis advising from Professor
John Hauser (motorcycle dynamics expert)
 Heat shielding of components
 Rubber shock and vibration damping mounts
High-Level Block Diagram
Questions??
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