Questions about Stretch - external hardware and speed of movement of DoFs

Discuss
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I had a few questions we hoped to find answers for -

  1. Is there a way to mount an IPad/tablet on Stretch? If yes, could that also be controlled through ROS or code provided with Stretch? (I am thinking of a use case where the tablet has a display that acts as a face for Stretch)
  2. Would it be possible to know what are the speeds of movement for each of the DoFs?
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Hi @rishi, there’s an end-effector available in the Stretch Tool Share repository that we’ve used to mount a phone to the robot. It’s called the Phone Holder V1. You could use this end-effector for an iPad or tablet by switching out the phone holder, which attaches via standard screw mount for tripods: 1/4"-20 tpi, for a tablet holder with the same standard tripod screw mount. For example, this holder on Amazon might work.

Note that we’ve haven’t tried mounting a tablet on Stretch, so I would consider the weight and dimensions of the tablet & holder. We recommend the payload doesn’t exceed ~3.3 lbs. The holder attaches to a swiveling joint (called the “Wrist Yaw” joint), so ensure the dimensions of the tablet/holder don’t collide with the arm. You can control the wrist yaw joint in ROS and in python.

You can control the speed of movement for every joint on the robot, both in ROS or using the python stretch_body library. You can find details on the max speed of movements for each joint in the specifications section on the product page. In particular, the lift and arm have a max speed of 0.2 m/s, while the base has a max speed of 0.6 m/s.