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status data

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JamesNewton edited this page Jul 31, 2018 · 28 revisions

Dexter status data

The status of the Dexter robot arm is returned to DDE by the Firmware after every command. All the _DELTA and _AT values are scaled by the calibration values in the AxisCal.txt file. DDE calculates additional status data and adds it to the status array1 available to jobs. This includes slope values for each joint.

The actually returned data includes:

  • DMA_READ_DATA
  • DMA_READ_DATA
  • RECORD_BLOCK_SIZE
  • END_EFFECTOR_IO_IN

In April 2018, the FPGA code was changed so that:
SLOPE_BASE_POSITION is the position of Axes 6,
SLOPE_PIVOT_POSITION is force Axis 6,
SLOPE_END_POSITION is the position of Axis 7,
SLOPE_ANGLE_POSITION is force of Axis 7.

For each of the following:
*_AT - Current position goal. This is the position the motion controller has told the stepper to go to in this instant on it's way to the commanded position goal.
*_DELTA - Instantaneous error in position. Difference between _AT and actual position.
*_PID_DELTA - Accumulated corrective error signal. Force due to inertia, gravity, friction, etc...

*_FORCE_DELTA - In follow mode, this is the offset in position necessary to keep force at zero.
*_SIN - The current A2D value from the sin sensor on that joints encoder.
*_COS - The current A2D value from the cos sensor on that joints encoder.
PLAYBACK_ - Not used? The step and direction ticks sent to the motor in the time between status updates.
SENT_ - Little used? Commanded position goal.
SLOPE_ - Unused. Was rate of change of _AT. Measurement of joint speed.

  • BASE_POSITION_AT
  • BASE_POSITION_DELTA
  • BASE_POSITION_PID_DELTA
  • BASE_POSITION_FORCE_DELTA
  • BASE_SIN
  • BASE_COS
  • PLAYBACK_BASE_POSITION
  • SENT_BASE_POSITION
  • SLOPE_BASE_POSITION
  • PIVOT_POSITION_AT
  • PIVOT_POSITION_DELTA
  • PIVOT_POSITION_PID_DELTA
  • PIVOT_POSITION_FORCE_DELTA
  • PIVOT_SIN
  • PIVOT_COS
  • PLAYBACK_PIVOT_POSITION
  • SENT_PIVOT_POSITION
  • SLOPE_PIVOT_POSITION
  • END_POSITION_AT
  • END_POSITION_DELTA
  • END_POSITION_PID_DELTA
  • END_POSITION_FORCE_DELTA
  • END_SIN
  • END_COS
  • PLAYBACK_END_POSITION
  • SENT_END_POSITION
  • SLOPE_END_POSITION
  • ANGLE_POSITION_AT
  • ANGLE_POSITION_DELTA
  • ANGLE_POSITION_PID_DELTA
  • ANGLE_POSITION_FORCE_DELTA
  • ANGLE_SIN
  • ANGLE_COS
  • PLAYBACK_ANGLE_POSITION
  • SENT_ANGLE_POSITION
  • SLOPE_ANGLE_POSITION
  • ROT_POSITION_AT
  • ROT_POSITION_DELTA
  • ROT_POSITION_PID_DELTA
  • ROT_POSITION_FORCE_DELTA
  • ROT_SIN
  • ROT_COS
  • PLAYBACK_ROT_POSITION
  • SENT_ROT_POSITION
  • SLOPE_ROT_POSITION

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