Real-Time Physics Simulation Forum 2021-08-01T15:08:23+00:00 https://pybullet.org/Bullet/phpBB3/app.php/feed/topic/13252 2021-08-01T15:08:23+00:00 2021-08-01T15:08:23+00:00 https://pybullet.org/Bullet/phpBB3/viewtopic.php?p=43535#p43535 <![CDATA[Re: translation along link]]>

Code: 

    pos = [pos[0] + 0.5*camera_vector[0], pos[1] + 0.5*camera_vector[1], pos[2] + 0.5*camera_vector[2]]    pos = tuple(pos)
If anyone has a better way let me know

Statistics: Posted by djb — Sun Aug 01, 2021 3:08 pm

]]> 2021-08-01T14:38:27+00:00 2021-08-01T14:38:27+00:00 https://pybullet.org/Bullet/phpBB3/viewtopic.php?p=43534#p43534 <![CDATA[translation along link]]>
I've got an end effector and I'm setting up the camera on the end effector (length is 0.618)

So far I've taken some code from a grasping project, and added 0.3 to the Z height, which is a bit better, since the camera is sitting on the link.

But I would prefer if the camera were translated from its position, along the orientation, by 0.618

Anyone with some basic matrix skills able to help?

I presume it's like the

Thanks


Code: 

    pos = end_effector_state[0]     ori = end_effector_state[1]    #translate a bit higher    pos = list(pos)     pos[2] += 0.3    pos = tuple(pos)    rot_matrix = self._pybullet_client.getMatrixFromQuaternion(ori)    rot_matrix = np.array(rot_matrix).reshape(3, 3)   # Initial vectors    #init_camera_vector = (0, 0, 1) # x-axis    init_camera_vector = (0, 0, -1) # x-axis   - oops it was looking backwards    init_up_vector = (0, 1, 0) # y-axis    # Rotated vectors    camera_vector = rot_matrix.dot(init_camera_vector)    up_vector = rot_matrix.dot(init_up_vector)    #end_effector_length_vector = (0.618, 0, 0)    #camera_vector = rot_matrix.dot(end_effector_length_vector)    self.view_matrix_gripper = self._pybullet_client.computeViewMatrix(pos, pos + 0.1 * camera_vector, up_vector) #why 0.1?    img = self._pybullet_client.getCameraImage(256, 256, self.view_matrix_gripper, self.projectionMatrix, shadow=0, flags = self._pybullet_client.ER_SEGMENTATION_MASK_OBJECT_AND_LINKINDEX, renderer=self._pybullet_client.ER_BULLET_HARDWARE_OPENGL)

Statistics: Posted by djb — Sun Aug 01, 2021 2:38 pm

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