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Erik
Partner Posts: 2 Recruit
UR Force mode using values from an external sensor |
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Answered | |
/ Most recent by heingab
in Programming
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5 comments |

Hi all,
The UR Force mode in Polyscope is not enough accurate for some applications because the calculated forces at the TCP (based on the joints currents) are not accurate.
From Polyscope 3.3, it's possible to develop an URCap where an external force/torque sensor feeds its measurements directly into the UR force control loop.
Does anyone know if an URCap based on the FT300 has been already developed somewhere?
Thanks.
Erik
SYSAXES
The UR Force mode in Polyscope is not enough accurate for some applications because the calculated forces at the TCP (based on the joints currents) are not accurate.
From Polyscope 3.3, it's possible to develop an URCap where an external force/torque sensor feeds its measurements directly into the UR force control loop.
Does anyone know if an URCap based on the FT300 has been already developed somewhere?
Thanks.
Erik
SYSAXES
Tagged:
It is possible to feed the FT300 output in the UR force mode. This post sums it. You need to use RTDE in order to do so. As of today, the FT Sensor URCap does not include the functionality of streaming the sensor data in the UR force mode.
Product Expert
Robotiq
[email protected]
Thank you very much for your quick answer. In the other post, Samuel says it's has to be in your URCaps, do you know when it will be done?
One of our automotive customer needs it asap.
Thanks.
Erik
It will just be very nice when it is in the URCap as then it will be a simple plug and play kind of thing.
@Samuel_Bouchard this would be our primary use for a FT sensor in our applications, just getting better force feedback especially in the force node, any update on if this made the product roadmap you can share?
In the past months, we made it work internally and ran a series of test in order to measure the effect of feeding the force signal into the UR controller. The improvement for realistic use cases (e.g. polishing) was negligible and during our tests we realized that although the FT signal is sent to the controller, the control algorithm of the robot is not changed. As such, it generally doesn't provide a better force control.
The only use case that was improved significantly was using the force mode towards a fixed point, for example if the robot is pushing against a part up to a given force. However, this is already possible using our current URCap (if you do a move inside of a "if" statement monitoring the force continuously).
Because the gains were not significant, we decided not to include this feature inside of our FT URCap. That being said, we are open to feedback from people who have used it with success.
Nicolas Lauzier, Eng., PhD
R&D Director
[email protected]