Robot control part 4: Operation space control
In this post we’ll look at operational space control and how to derive the control equations. I’d like to mention again that these posts have all come about as a result of me reading and working...
View ArticleRobot control part 5: Controlling in the null space
In the last post, I went through how to build an operational space controller. It was surprisingly easy after we’ve worked through all the other posts. But maybe that was a little too easy for you....
View ArticleRobot control part 6: Handling singularities
We’re back! Another exciting post about robotic control theory, but don’t worry, it’s short and ends with simulation code. The subject of today’s post is handling singularities. What is a singularity...
View ArticleRobot control part 7: OSC of a 3-link arm
So we’ve done control for the 2-link arm, and control of the one link arm is trivial (where we control joint angle, or x or y coordinate of the pendulum), so here I’ll just show an implementation of...
View ArticleDynamic movement primitives part 3: Rhythmic movements
So far we’ve looked at using DMPs for discrete movements, but as I briefly mentioned it’s also possible to use them to perform rhythmic movements. In this post we’re going to look at the implementation...
View ArticleOperational space control of 6DOF robot arm with spiking cameras part 2:...
In the previous exciting post in this series I outlined the project, which is in the title, and we worked through getting access to the arm through Python. The next step was deriving the Jacobian, and...
View ArticleThe iterative Linear Quadratic Regulator algorithm
A few months ago I posted on Linear Quadratic Regulators (LQRs) for control of non-linear systems using finite-differences. The gist of it was at every time step linearize the dynamics, quadratize (it...
View ArticleUsing SymPy’s lambdify for generating transform matrices and Jacobians
I’ve been working in VREP with some of their different robot models and testing out force control, and one of the things that becomes pretty important for efficient workflow is to have a streamlined...
View ArticleFull body obstacle collision avoidance
Previously I’ve discussed how to avoid obstacles using DMPs in the end-effector trajectory. This is good when you’re controlling a single disconnected point-mass, like a mobile robot navigating around...
View ArticleImproving neural models by compensating for discrete rather than continuous...
This is going to be a pretty niche post, but there is some great work by Aaron Voelker from my old lab that has inspired me to do a post. The work is from an upcoming paper, which is all up on Aaron’s...
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