collision detection problem of collision shape controlled by haptic device
Posted: Sat Dec 09, 2017 4:08 pm
Hi everyone,
I have a question about the collision detection between a softbody and a rigid body.
Here is what I'm trying to do. The bottom of the softbody is attached to the ground, so it cannot be moved but can be still deformed. The rigid body is controlled by a haptic device, so the user can move it anywhere. The rigid body is a L shape handle that is simplified with two implicit collision shapes--capsule. If the user touches the softbody with a slow motion and gentle force, the collision detection works regularly. However, when the user uses a brutal force and pushes hard against the softbody, it will totally penetrate into the softbody.
So, my question is, is there any collision detection and resolution for collision shape? It seems not to me, when the collision shape pushes the softbody, there is collision detection and resolution for the softbody, so the softbody knows when the collision happened and how to respond after. However, it seems no collision resolution for the collision shape, when the user pushes against the softbody to it's maximum deformation, somehow, there should have a way to adjust the transformation of the collision shape from keeping moving forward and penetrating into the softbody.
Can bullet solve this problem or am I wrong? I found the samething in Nvidia Flex. Also, in all the related papers, most of the papers are talking about collision detections between virtual objects. There are hardly any paper talking about the collision detection and resolution for a rigid collision shape controlled by a haptic device. Hope someone can help me understand this problem.
Also I have some general questions about Bullet?
1. Does bullet physics use force-based dynamics or position-based dynamics? If it's position-based, I didn't see any particles. In Nvidia Flex simulator, you can visualize all the particles on a softbody or rigid body. Also, are the particles the vertices of the object mesh? In Nvidia, all the particles are sampled all over the body volume, not just on the surface.
2. How to change the camera view in Bullet? Currently, I only know how to zoom in/out by scrolling the mouse wheel. Is there a way to look up/down/left/right? Or change camera position?
Thanks!
I have a question about the collision detection between a softbody and a rigid body.
Here is what I'm trying to do. The bottom of the softbody is attached to the ground, so it cannot be moved but can be still deformed. The rigid body is controlled by a haptic device, so the user can move it anywhere. The rigid body is a L shape handle that is simplified with two implicit collision shapes--capsule. If the user touches the softbody with a slow motion and gentle force, the collision detection works regularly. However, when the user uses a brutal force and pushes hard against the softbody, it will totally penetrate into the softbody.
So, my question is, is there any collision detection and resolution for collision shape? It seems not to me, when the collision shape pushes the softbody, there is collision detection and resolution for the softbody, so the softbody knows when the collision happened and how to respond after. However, it seems no collision resolution for the collision shape, when the user pushes against the softbody to it's maximum deformation, somehow, there should have a way to adjust the transformation of the collision shape from keeping moving forward and penetrating into the softbody.
Can bullet solve this problem or am I wrong? I found the samething in Nvidia Flex. Also, in all the related papers, most of the papers are talking about collision detections between virtual objects. There are hardly any paper talking about the collision detection and resolution for a rigid collision shape controlled by a haptic device. Hope someone can help me understand this problem.
Also I have some general questions about Bullet?
1. Does bullet physics use force-based dynamics or position-based dynamics? If it's position-based, I didn't see any particles. In Nvidia Flex simulator, you can visualize all the particles on a softbody or rigid body. Also, are the particles the vertices of the object mesh? In Nvidia, all the particles are sampled all over the body volume, not just on the surface.
2. How to change the camera view in Bullet? Currently, I only know how to zoom in/out by scrolling the mouse wheel. Is there a way to look up/down/left/right? Or change camera position?
Thanks!