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Student

You could use the spiral search with the built-in force monitoring. It's not as precise as an external FT sensor but may work. 

How repeatable/precise is is the measurement coming from the camera?  Understand the robot only has a precision of .004"/0.1mm so if your hole tolerance is less than that the robot will have a hard time anyways. 

Another option without seeing your gauge is to provide some lead-in on the edge of the gauge and then allow the robot to float in the XY directions while you move the gauge in the Z direction allowing the gauge to find its own way into the hole.  You would use the force wizard and a frame motion type to achieve this. 
@matthewd92 Thanks for your response.

I don't know exactly what you mean in your third paragraph. And how can I implement the spiral search in Polyscope?

Thanks!

matthewd92

@Student So here are a couple of examples of using a pin to gauge a hole.  The first image is of a standard type pin gauge, where there is a nice square corner which you as a human can still easily handle.  The second shows the gauge having some lead-in, quite exaggerated in this example.

zoom

zoom

As you can imagine its much easier to get the second one started in the hole.  By using the Force wizard you can place a waypoint inside of a force node and allow the robot to float in the XY directions if you are for example moving in the Z direction to insert the pin.



As far as how to implement the spiral search in polyscope refer to
this post.  The difference is you will need to place into a background thread a feature to find the forces on the robot

Thread
  forceOnArm = get_tcp_force() #This returns a list of forces in X,Y,Z, Rx, Ry, Rz on the TCP
  Fx = forceOnArm[0]
  Fy = forceOnArm[1]
  Fz = forceOnArm[2]
  sync()

 
You could the just substitute this into program that @Tyler_Berryman produced.  The thread where the idea Tyler did came from is located here

Hope this helps

Karine_Simard

Thanks! Nice work!