Measure screwing torque with FT300

Catherine_Bernier 2016-09-30

I got a request from a customer about being able to measure the torque in a screwing application.

It's a good application for our FT300 since you are able to monitor and even trigger a second event once you reach the torque desired.

The minimal torque detection threshold for the FT 300 is 0.12 Nm in the Z axis. You can see the spec sheet here.

For a bit better resolution, we also have the FT150. Here is the spec sheet.

Note that the sensor reads the torque at a rate of 100 Hz and that the screwing tool might induce some vibrations to the sensor.

From your experience Pros, did you use our FT sensor in screwing applications?

Catherine_Bernier 2016-11-18

I can add that you want to make sure not to have a damper between the FT300 and the screw to measure the right torque. You also don't want high RPM tools since the 100Hz of data acquisition can not be enough to react when the force is reached.

Sebastien 2016-11-21

@Catherine_Bernier
Many people worked on screwing solutions for robotics applications. Based on experience what clients are looking for in such applications is:

Cycle time: They usually want to do this as fast as possible since it will affect their ROI. So we need RPM on the screwing tool.
Feeding of the screws/bolts: There are some self feeding systems already out there. Designing such a system could take a lot of time so we usually buy of-the-shelf products with self feeding technology. However, we have to be careful in the selection and often require the supplier to run some testings with the client's parts before purchasing.
Most systems also offer built-in torque measurements which reduces the time of integration if we were to compare to using the FT300 or FT150.

However, were I think the FT300 could come handy is if a client would not want to screw but instead run quality check on the torque of some screws. Some assembly applications are hard to automate because of the complexity of part handling and insertions so they are still assembled by humans. However, having a robot go the repeatable screw positions and simply checking screwing torque for quality purposes could be a good and simple applications. Any pros saw a similar application?