Grasping simulation

Hi is there a 3 to 5 fingers grasping example in DART so that we can have a look? Thanks!

Don’t have an example of grasping simulation at the moment, but it would be great to have. I’ll add one when having a chance. If you can make one, pull request is always welcome!

Sorry to be late to the conversation, but I thought I’d mention:

Grasping in a rigid body dynamics simulator can be very messy, because the contact forces and collision handling in grasps tend to lie in a different mathematics regime (static equilibrium) than what a rigid body dynamics simulator tends to use.

If you want to simulate a grasp within a rigid body simulator, I would recommend doing a bit of a “hack” where you come up with some criteria to decide if the object should be considered “grasped”, and then create a WeldJoint between the object and the palm of the robotic hand. That WeldJoint will emulate a static equilibrium of contact points, and then you can move the object around freely.

If you want to simulate a particularly complex kind of grasp that can’t just be modeled as a fixed constraint, then you’ll need to do a lot of careful tuning of parameters in your simulation (like the restitution and friction coefficients) and be very careful about what forces you command to the fingers.

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