Category : drake

I am having fun with pydrake for the region of attraction (RoA) analysis. There is one type of non-linear system involving trigonometry that got me stuck. A similar problem has been posted here. As Russ points out in that post, there are 2 solutions: 1) shifting to another state-space; 2) using Taylor expansion. I am ..

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Newer Drake user here. We’re setting up a ping pong playing iiwa, but we’re getting the following error when the ball and paddle come in contact. IndexError Traceback (most recent call last) /tmp/ipykernel_3391/3824908623.py in <module> 94 95 # simulator.AdvanceTo(0.9) # works —> 96 simulator.AdvanceTo(1.0) # fails when the ball and paddle come in contact IndexError: ..

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I’m currently working on a trajectory optimization problem that involves binary actuators. In order to avoid solving an MINLP I do not simply optimize over the states and control inputs but instead, assume that each of the binary actuators alternates between the states "on" and "off" and optimize over the duration of those intervals. I ..

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I’m a student teaching myself Drake, specifically pydrake with Dr. Russ Tedrake’s excellent Underactuated Robotics course. I am trying to write a combined energy shaping and lqr controller for keeping a cartpole system balanced upright. I based the diagram on the cartpole example found in Chapter 3 of Underactuated Robotics [http://underactuated.mit.edu/acrobot.html], and the SwingUpAndBalanceController on ..

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