RTDE actual_tool_accelerometer value

Hi all,

i’m trying to get the actual acceleration of the tcp by using the mentioned RTDE Output.
Depending on how the tool flange is oriented, one or two axis are always accelerating, according to the output values, although it is not moving at all and the actual_TCP_speed values are zero.
Is this somehow because of the gravitational acceleration? Can anyone explain to me how these RTDE values are generated?

Thanks in advance!

Hello @marvin.fink,

From what I remember the get_tool_accelerometer reading was implemented to be used internally to verify the mounting configuration of the robot. It’s sample rate was very low. This makes me think that the effects you are seeing are due to gravitational acceleration.

The value, having a low sample rate, is not very accurate. What is the use case or task you are aiming to accomplish with this functionality? You may need a more precise method to measure the accelerations depending on your needs.

Thanks for your answer @inu.

That’s what I expected.
In my setup , there is a heavy tool mounted at the flange, that gets in contact with a surface. If the contact is made, the freedrive mode will be activated for a few seconds. I tried different RTDE values and data of our FTS to check how the tool is moving and changing its position in this freedrive phase.
Other values seem to be more precise und useful for this but I was just wondering about the accelorometer.

are these values calculated or measured?