RBE Ph.D. Dissertation Defense: Vinayak Jagtap | A Walking Controller for Humanoid Robots using Virtual Forces

robotics_banner.jpg

Various images of robots at Robotics Engineering WPI alt
WPI Robotics Engineering
Friday, September 13, 2019
11:00 am to 12:00 pm
Floor/Room #: 
Suite 201, RBE 209 (Conference Room)

RBE Ph.D. Dissertation Defense

A Walking Controller for Humanoid Robots using Virtual Forces

Vinayak Vasantrao Jagtap

 

Friday, September 13, 2019

11:00 am - 12:00 pm

Suite 201, 85 Prescott St. | Robotic Conference Room 209

 

Abstract: Current state-of-the-art walking controllers for humanoid robots use simple models, such as Linear Inverted Pendulum Mode (LIPM), to approximate Center of Mass(CoM) dynamics of a robot. These models are then used to generate CoM trajectories that keep the robot balanced while walking. Such controllers need prior information of foot placements, which is generated by a walking pattern generator. While the robot is walking, any change in the goal position leads to aborting the existing foot placement plan and re-planning footsteps, followed by CoM trajectory generation. This thesis proposes a tightly coupled walking pattern generator and a reactive balancing controller to plan and execute one step at a time. Walking is an emergent behavior from such a controller which is achieved by applying a virtual force in the direction of the goal. This virtual force, along with external forces acting on the robot, is used to compute desired CoM acceleration and the footstep parameters for only the next step. Step location is selected based on the capture point, which is a point on the ground at which the robot should step to stay balanced. Because each footstep location is derived as needed based on the capture point, it is not necessary to compute a complete set of footsteps. Experiments show that this approach allows simpler inputs, faster operation, and inherent immunity to external forces from the environment. Experiments are performed on Boston Dynamic's Atlas robot and NASA's Valkyrie R5 robot in simulation, and on Atlas hardware.

Ph.D. Advisor:           Professor Michael Gennert (WPI)

Ph.D. Committee:     Professor Gregory Fischer (WPI), Professor Mohammad Mahdi Agheli Hajiabadi (WPI), Professor Taskin Padir (Northeastern University)

DEPARTMENT(S): 
Name: 
Kristen Bronger, RBE Administrative Assistant
Phone Number: