Rethink Robotics Sawyer, Original Instructions Manual, Page: 113 / 220

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Intera 5.3
Force Sensing and Selective Arm Stiffness
Force Sensing and Selective Arm
Stiffness
For the latest and most detailed information on Sawyer and Intera 5, we always recommend you
see the Online User Guide at:
mfg.rethinkrobotics.com/intera. The Rethink Robotics support page
is here: Rethink Support.
As of Intera 5, Sawyer can sense and measure force on the robot end point. It can therefore react to
outside conditions, as well as make use of its own measured force when performing tasks. In
addition, it is now possible to select how stiff the arm should be per axis, and the maximum amount
of force the robot may use when trying to reach a point in space.
With force sensing, Sawyer can actually change what parts of a task it will perform based on the
kind of force acting upon it (for example, from which direction, and/or how much force.) For
example, you may be able to train Sawyer to take different strategies when inserting a part into a
fixture depending on when and what forces are being sent. This will allow the robot to better deal
with part and process variation. The selective stiffness will also help with this process.
A Practical Application for Using Force Sensing, Selective Stiffness, and Force Limitations
Sawyer can be trained to inspect how securely a wire is connected to an engine. Sawyer grabs and
pulls on the wire (using selective stiffness to deal with how the wire is situated in space and limiting
the force applied so the robot doesn’t inadvertently pull the wire) with a force defined in its task. If
the wire is not pulled out by that amount of force (sensing the desired force), it passes inspection.