Just to give you a flavour for the topic. I have a picture of a space shuttle arm. Here you can see that the space shuttle arm is grabbing one satellite and trying to deploy it. Even from this picture you can see that it is bent. So, it deforms under the weight of the satellite or when it is trying to move the satellite. This bending is very different from manipulators on earth where a manipulator can be very easily modelled as a rigid object with rigid elements.

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