Design Strategy for MITEE Mouse 9

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Design Strategy for MITEE Mouse 9

• MINOS 03
• Royal Holloway
• David Otten

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Features

• Low Inertia
• Low Center of Gravity
• Increased Clearance on Diagonals
• Improved Sensor Placement
• Accelerometers
• Torque (current) Measurement
• Fan

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MITEE 8
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MITEE 9
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Wheel Speed during a Turn
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Figure of Merit for Turning
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Design 0
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Design 1a
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Design 1b
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Summary 1
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Summary 2
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Summary 3
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MITEE 8 Sensor Configuration
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MITEE 9 Sensor Configuration
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Improved Sensor Placement

• Pros
• Optimized for both straight and diagonal
  operation
• Sensors able to look ahead
• Simultaneous sampling of all 4 posts on straight
  sections
• Reduced inertia
• Dual 12-bit A/Ds for improved resolution and
  sampling speed

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Improved Sensor Placement

• Cons
• Low S/N because of longer distance to wall and
  poor angle of reflection
• Heading, offset, and forward position errors
  interact

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Right Front Sensor Output
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Right Front Sensor Error
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Accelerometer

• Centrifugal Acceleration v2/R
• If the radius of a turn and the velocity of the
  mouse are known, the acceleration is known.
• If the acceleration is not the anticipated value
  and the speed is correct, the mouse may be
  slipping and traveling on a larger radius turn.

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Torque Measurement

• For a DC motor the torque is proportional to the
  current.
• The torque should also be proportional to the
  acceleration
• If the torque is not equal to the expected value,
  the mouse is not accelerating as expected and may
  be slipping

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Fan

• Active down force generation as an alternative
  to the ground effects or wings used on race cars

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Fan Performance
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Left Back Sensor Output
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Left Back Sensor Error
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MITEE 10