Robo-Roach – a six legged goal-directed

Subject: Autonomous Unmanned Aerial Vehicle Swarms: Optimal Self-Organization and Control for Search and Hunt Missions
Date: 1 September 2009
Faculties: Faculty of Mechanical Engineering
  Faculty of Electrical Engineering
Researchers: Professor Ron Meir and Associate Professor Miriam Zacksenhouse

Abstract:

Dynamically stable legged robots are promising to provide significant advantages in navigating unstructured terrain. This capability makes them suitable for a range of important applications in surveillance, terrain exploration, rescue missions and service.
Dynamically stable legged robots are commonly controlled by networks of coupled oscillators, which model the biological central pattern generators. These systems are capable of autonomously generating and, most importantly, preserving the desired gait despite disturbances. However, disturbances do affect the direction and speed of motion, so while movement continues, the goal-directed behavior is sacrificed. Thus, additional control strategies are needed to modulate the gait and correct the speed and direction of movement.
Here we propose to integrate event-based sensory feedback to track and modulate the gait. Gait modulation is expected to reduce the effect of disturbances on the planned trajectory, and gait tracking to support self-tracking, These capabilities are critical for autonomous goal directed behavior.
Specifically, the timing of leg touch-downs will be detected using simple force sensors incorporated in the legs. These events will be used as direct or indirect inputs to the network of coupled oscillators, for gait tracking and adaptation. This proposal is motivated and extends our successful application of a similar approach to the control of a robotic yoyo.
More generally, legged locomotion is an example of hybrid dynamical systems in which the continuous-time dynamics change at discrete events (here leg touch-downs and lift-ups). In this framework, the long term goal of this proposal is to investigate the use of event-timing for controlling hybrid systems.