Walking control

Footstep planning, Future prediction

We are interested in predicting future states of the robot as fast as possible so that to be able to replan in case of strong perturbations. To this aim, we restrict the space of actuation and mimic a simple Linear Inverted Pendulum (LIP). Such simplification allows us to predict future steps easily and we can then use Model Predictive Control (MPC) on footstep planning to control energy of the robot and stability properties. Such framework brings high flexibiltiy and rosutness against various internal and external disturbances as well as strong pushes. 

We are basically interested in extending the formulation of this problem so that to handle slopes, rough terrains, stairs and etc. 

 

3LP

3LP is a 3D walking model we have recently developed with certain equations and properties to replace our traditional inverted pendulum. Please find movies of 3LP and arXive preprints of papers bellow.

Source codes: https://ponyo.epfl.ch/gitlab/salman.faraji/3LP

Publications

The foot-step planner was first applied to the Atlas robot in Gazebo, published in ICRA 2014

It was then applied to Coman robot in webots, published in RSS 2014

Here is also results on transfering the balancing method to the real robot, published in IROS 2015

An extension of the approach to extimate external forces is also submitted to IROS 2016

We are currently working to perform walking as next step.

 

Feel free to contact us in case you think of possible collaborations.

salman dot faraji at epfl dot ch

A long list of student projects is also available here under humanoids category.

Compliant and adaptive control of a planar monopod hopper in rough terrain

 

Versatile and robust 3D walking with a simulated humanoid robot (Atlas): A model predictive control approach

 

Robust and Agile 3D Biped Walking With Steering Capability Using a Footstep Predictive Approach

 

Practical considerations in using inverse dynamics on a humanoid robot: torque tracking, sensor fusion and Cartesian control laws

 

Designing a virtual whole body tactile sensor suit for a simulated humanoid robot using inverse dynamics

 

3LP: a linear 3D-walking model including torso and swing dynamics

 

A new time-projecting controller based on 3LP model to recover intermittent pushes

Singularity-tolerant inverse kinematics for bipedal robots: An efficient use of computational power to reduce energy consumption

Modeling robot geometries like molecules, application to fast multi-contact posture planning for humanoids