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Author Topic: wrist mounted force sensor  (Read 624 times)

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Offline mjroboticsTopic starter

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wrist mounted force sensor
« on: January 18, 2013, 04:06:15 AM »
Hi everyone,

I am about to use a wrist mounted 6DOF force/torque sensor. The sensor module is between a robot arm (7DOF articulated arm) and a gripper. My question is, what is the standard way to compensate for the effect of gripper weight and inertia of robot? I would like to measure only the external forces(i.e when the robot arm or gripper hit something or press on a surface), not other forces that affect the sensor.

Thanks.

Offline newInRobotics

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Re: wrist mounted force sensor
« Reply #1 on: January 18, 2013, 04:22:56 AM »
First thought is to do it in software. Read force sensor value with gripper being empty/not pushing against anything and set that as threshold value. If threshold value is exceeded, You know that some sort of load is applied to the gripper. Or is everything more complex than that?
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Offline mjroboticsTopic starter

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Re: wrist mounted force sensor
« Reply #2 on: January 18, 2013, 04:39:19 AM »
Thanks for reply,

It is actually more complex. In static case, the only problem seems to be the weight of gripper. Even in this case, you have the effect of weight, on different axes of force sensor. More problem is when the robot is moving, and due to acceleration and dynamics, there are forces measured by force sensor.

Actually, my question is first to know what sources of error could be, and then what are the "standard" solutions to them. I assume that there are lots of people who use wrist mounted force/torque sensors., and they should have the same problems, and should have solved it.

One guess would be to calculate the Weight and dynamics of robot at each step, and use them to compensate for the robot. But, I'm not sure if this is what everyone does.


 


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