Handbot/Real robot information

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General information

For general information such as how to compile the framework, connect etc. please refer to Footbot/Real robot information

Actuators

Arms

Initialisation

When the arms actuator is created (requested in XML configuration file), the robot performs an initialisation procedure with the goal of calibrating the encoders to zero. This is needed in order to have the PID control on the motors working properly. The initialisation procedure consists in:

  • Grippers are first closed and the opened completely
  • Arms are first completely retracted towards the body and then extended 2/3 the way
  • ADD INFO ABOUT HEAD AND GRIPPER ROTATION ONCE AVAILABLE

The arms and the grippers need to be free of moving without encountering any obstacle, otherwise the initialisation is not correct and arms actuators will not work properly. Once the initialisation procedure is finished the handbot configuration ("zero position") is the following:

  • Grippers completely opened, the claws forming an angle of 180 degrees between them
  • Grippers rotation such that the claws are perpendicular to the ground, reset button looking outside
  • Arms extended to form an angle of 40 degrees (the angle is 0 when the arms are fully retracted, 60 degrees when fully extended)
  • Head rotation such that the arms are parallel to the ground

Ranges

Each part of the arms can be actuated giving values in the range (refer to the "zero position" mentioned above):

  • Gripper aperture: from 180 (completely open) to 0 (completely closed)
  • Gripper rotation: from -90 to 90. Positive values: counter clockwise rotation looking from the gripper towards outside.
  • Arms aperture: from 0 (completely retracted) to 60 (completely extended)
  • Head rotation: LIMITS NOT KNOW AT THE MOMENT. Positive values: clockwise rotation looking from the head towards outside.

The values represent angles in degrees, the user is free send commands outside the limits, but the ASEBA backend will limit the actual value sent to the PID and therefore the position reached by the corresponding part.

Notes

  • With the first handbot prototype sometimes the arms shake when a value is actuated. When this happens gently move the arm towards the goal position and normally it stops shaking.
  • All the commands sent to the actuators by the controller before the completion of the initialisation procedure will be ignored.

LEDs

TODO: FILL INFORMATION

Beacon (launcher LEDs)

TODO: FILL INFORMATION

Sensors

Encoders

The encoders readings are the angular positions of all the parts of the arms, please refer to the arms actuator. Important: the encoders provide meaningful readings only after the arms initialisation procedure is finished. This means that in case the initialisation is not performed (arms actuator not declared in XML configuration) the readings from the encoders are always zero.


Proximity sensors

TODO: add information on range + reading max-min values.