I'll be implementing few algorithms in Underactuated Robotics and also solving some interesting problems
- List of Custom Environments
- Quadrotor-2D
- CartPole Continuous
- Double Integrator
- Pendulum with Vibrating Base
The below is a list of custom environments that I built using OpenAI gym, feel free to use them however you want
Consider here an extremely simple model of a quadrotor that is restricted to live in the plane. The equations of motion are almost trivial, since it is only a single rigid body, and certainly fit into our standard manipulator equations:
LQR here works essentially out of the box for Quadrotors, if linearized around a nominal fixed point (where the non-zero thrust from the propellers is balancing gravity). In this case nominal fixed point is
The here task is to balance a simple pendulum around its unstable equilibrium, using only horizontal forces on the cart. Balancing the cart-pole system is used in many introductory courses in control because it can be accomplished with simple linear control (e.g. pole placement) techniques. Consider the full swing-up and balance control problem, which requires a full nonlinear control treatment.
Consider the double integrator system
If you would like a mechanical analog of the system, then you can think about this as a unit mass brick moving along the x-axis on a frictionless surface, with a control input which provides a horizontal force, u . The task is to find a policy for the system where, to regulate this brick to .
Consider here an actuated pendulum whose base (pivot of the rod) is forced to oscillate horizontally according to the harmonic law , where h denotes the amplitude of the oscillation and ω the frequency. The equation of motion for this system is
The goal is to design a time-dependent policy that makes the pendulum spin at constant velocity ,
below is the result through feedback cancellation,