2d sliding joint with floor (or plane) ?
Posted: 27 Aug 2013, 00:43
I'm interested in putting together a model that uses a 2d sliding constraint. Specifically, I'd like to constrain the end of the spring to be on a surface, such as a plane or just the ground plane, and the other end to be rigidly attached to a shape (no spherical joint, cantilevered joint effectively). What's the best way to go about constructing something like this?
I'm not sure if I should be using the GCS solver and link dummies, or with a simpler construction.
Here's my attempt to get it working using the joint in IK mode and the GCS solver, as well as a child sprint that constantly updates the position of a "floorFollower" dummy:
https://www.dropbox.com/s/wjji7rf5irmpn ... 20test.ttt
The idea there is that once the spring is working properly, with a high spring constant and high friction, the friction will hold the object on the slope, or at least the spring tension will resist the rotation & rolling of the object on the slope.
(this is a contrived example of a larger robot model, of course).
Even if I can get the GCS & IK solver to work, I wouldn't be able to put the joint into motor/PID/spring mode, would I?
The only other thought I have is to put two perpendicular prismatic joints as children of the floor, set their motion range to be very high, and then somehow get the "springEnd" dummy or a hidden object at the end of the spring to be linked to the planar 2DOF created by those floor joints.
I'm not sure if I should be using the GCS solver and link dummies, or with a simpler construction.
Here's my attempt to get it working using the joint in IK mode and the GCS solver, as well as a child sprint that constantly updates the position of a "floorFollower" dummy:
https://www.dropbox.com/s/wjji7rf5irmpn ... 20test.ttt
The idea there is that once the spring is working properly, with a high spring constant and high friction, the friction will hold the object on the slope, or at least the spring tension will resist the rotation & rolling of the object on the slope.
(this is a contrived example of a larger robot model, of course).
Even if I can get the GCS & IK solver to work, I wouldn't be able to put the joint into motor/PID/spring mode, would I?
The only other thought I have is to put two perpendicular prismatic joints as children of the floor, set their motion range to be very high, and then somehow get the "springEnd" dummy or a hidden object at the end of the spring to be linked to the planar 2DOF created by those floor joints.