Quadruped locomotion

The aim of this project is to develop a complete framework that can autonomously generate, adapt, control and plan complex motor behavior for articulated robots with many degrees-of-freedom (DOFs) .
We focus the topical issue of robust, flexible and adaptive goal-directed quadruped locomotion in unknown, irregular terrain, modeled as discrete, sensory-driven corrections of the locomotion rhythmic patterns.
We address the problem of developing a closed-loop controller architecture inspired in the functional model of biological motor systems that can online and autonomously generate and adapt movements that have both discrete and rhythmic primitives.

The proposed architecture will be able to independently:

  1. Generate different gaits
  2. Select and switch between the gaits according to the sensed situation (for instance speed) and/or the behavioral context
  3. Online adapt gait and posture to the environment and body changes
  4. Adapt to perturbations and uncertainties
  5. Steering
  6. Reaching
  7. Online reduce locomotion-induced head movement

It uses dynamical systems theory for:

  1. Generating complex movements that smoothly superimpose and/or switch between discrete and rhythmic primitives
  2. Easily control the switch between the possible movements
  3. DOFs coordination
  4. Easily integrate multiple types of sensor-feedback pathways
  5. Modulate the movements according to these feedback pathways
  6. Planning.
People involved in this research: 
Related publications: 
Castro, L., C. P. Santos, M. Oliveira, and A. Ijspeert, "Postural Control on a Quadruped Robot Using Lateral Tilt: A Dynamical System Approach", European Robotics Symposium 2008, vol. 44: Springer Berlin / Heidelberg, pp. 205-214, 2008.  Download: castro_euros_2008.pdf (623.77 KB)
Santos, C. P., and V. Matos, "Gait Transition and modulation in a quadruped robot: A brainstem-like modulation approach", Robotics and Autonomous Systems, vol. In Press, Accepted Manuscript, pp. -, 2011.
Matos, V., and C. P. Santos, "Omnidirectional locomotion in a quadruped robot: A CPG-based approach", Intelligent Robots and Systems (IROS), 2010 IEEE/RSJ International Conference on, pp. 3392 -3397, oct., 2010.  Download: Omnidirectional Locomotion in a Quadruped Robot: A CPG-based Approach (224.26 KB)
Sousa, J., V. Matos, and C. P. Santos, "A bio-inspired postural control for a quadruped robot: An attractor-based dynamics", Intelligent Robots and Systems (IROS), 2010 IEEE/RSJ International Conference on, pp. 5329 -5334, oct., 2010.  Download: A bio-inspired postural control for a quadruped robot: an attractor-based dynamics (229.91 KB)
Matos, V., C. P. Santos, and C. M. A. Pinto, "A brainstem-like modulation approach for gait transition in a quadruped robot", Intelligent Robots and Systems, 2009. IROS 2009. IEEE/RSJ International Conference on, pp. 2665 -2670, oct., 2009.