Concepts about bolting task

Technical Questions
1

Hello, I am developing a bolting task.
I watched this webinar (Atornillado Colaborativo) sorry is in Spanish.
However, the most important is the analysis of some points with high-torque screwdrivers. I summarize the following points:

  1. avoid having the Z-axis of the tool parallel to the Z-axis of the tool flange, the 90-degree offset will reduce stress on the joints.
  2. Includes a spring or other mechanical compensation to allow the screwdriver tip to follow the fastener head while tightening so that the robot is at complete rest during the task.
  3. Ensure a distance of 20 to 40 cm between the center of the flange and the TCP to reduce the bolting reaction force.
  4. Uses 90 degrees between mounting and tooling directions, with two points of clamping.
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I understood points 1, 2, and 4, but I don’t understand the reason behind point 3.
Could you help with an explanation or some paper?

thanks

2

I can’t give you an answer to point 3, either. I don’t see why that is necessary. :slight_smile:

However, I would like to add to point 1, that a 45-degree angle is better than 90 degree, as far as I know. Then you won’t risk getting into singularities and should always have the option to use the built-in force functions (which is not possible close to singularity).