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Task Space Planning with Obstacle Avoidance

Now we want to add an obstacle to our environment. The obstacle is located at $ [0.5, 0.5]$ in Cartesian space. For simplicity, we assume that only the end-effector can collide with the obstacle. The collision probability $ P(c_t = 1\vert q_t^{(j)})$ for joint position $ \mathbf{q}^{(j)}$ is given by $ \exp(-1/2 \vert\vert\Phi(\mathbf{q}^{(j)}) - [0.5, 0.5]^T\vert\vert^2 / 0.15^2)$ . We want our robot to avoid the obstacle for the whole trajectory, therefore we add the observation of not colliding with the obstacle $ P(c_t = 0\vert q_t^{(j)})$ for each time step $ t$ to our Bayesian network (see Figure 11, $ c_t$ notes).

Figure 11: Dynamic Bayesian Network for planning with obstacles.
Image linear_state_space_models



Haeusler Stefan 2011-01-25