Alt text

Google scholar
(shishir k)olathaya at iisc dot ac dot in

For email: use only the letters in perentheses and no spaces.

About me

I am an INSPIRE Faculty fellow in the Robert Bosch Center for Cyber Physical Systems (RBCCPS) in IISc Bangalore. I received my Ph.D. degree in Mechanical Engineering (2016) from the Georgia Institute of Technology. I am interested in stability and control of nonlinear hybrid systems, especially in the domain of legged robots. I have worked with robots like AMBER1, AMBER2, DURUS-2D, and DURUS. I currently have following major activities:

  1. I have been recently exposed to safety-critical control in all kinds of robotic platforms. Control barrier functions (CBFs) have proved to be extremely effective in real-time QP based controllers. I am currently focusing on introducing some notion of robustness for these safegaurding controllers. The notion of robustness for safety is still in its nascent stages. Watch the video below where a tunable gain (epsilon) is varied to make the drone more and more conservative in safety.
  2. The brown square indicates the "safe" region, and the destination is outside this region. Due to GPS estimation errors, the drone overshoots from the boundary. Therefore, the goal of the controller is to take corrective actions to overcome this overshoot.
  3. Deep learning is getting a lot of attention of late. I am currently in the phase of understanding deep reinforcement learning (D-RL) and see how it can be applied to legged robots. This is in collaboration with Dr. Bharadwaj Amrutur, Dr. Shalabh Bhatnagar and Dr. Ashitava Ghosal in the center. See video below of our most recent walking result! Gaits were generated via D-RL based training, and then implemented via kinematic motion primitives.
  4. I am interested both in theoretical and practical aspects of hybrid robotic systems. My PhD dissertation was about bridging the gap between theory and experiment by using input-to-state stabilizing control Lyapunov functions (ISS-CLFs). I am looking to extend it for various other robotic platforms and also develop novel robust controllers based on this idea.

Select publications

This was one of my first publications that appeared as a chapter in Springer.

S. N. Yadukumar Kolathaya and M. Pasupuleti and A. D. Ames. From Formal Methods to Algorithmic Implementation of Human Inspired Control on Bipedal Robots. 2013. Chapter in Algorithmic Foundations of Robotics X. .pdf .bib .video

This is my most recent publication, which is about how to define the notion of input-to-state safety in nonlinear systems:

S. Kolathaya and A. D. Ames. Input-to-State Safety With Control Barrier Functions. 2018. IEEE Control Systems Letters. Volume 3, Issue 1, Pages 108-113. .pdf .bib