A modular worm-like robot has been constructed, capable of moving in a straight line, using a wave propagation gait. Locomotion controller is based on control tables, automatically generated from the parameters of the waves applied: waveform, amplitude and wavelength. Locomotion is achieved by means of the propagation of these waves along the worm, from the tail to the head. Higher level software just need to specify this parameters to locomote the robot.
The controller has been implemented on a low cost FPGA using custom cores, described in VHDL, together with the MicroBlaze soft-processor, where the algorithms are executed. FPGAs increases the robot versatility so that the designer can select the architecture that better fix the requirements. Main limitations of this approach are the memory and FPGA resource availability. The main advandages are: possibility of implementing new architectures, faster control algorithms, dinamyc hardware modification, hardware/software codesign, and remote hardware reconfiguration.
A working platform has been developed. Current research is focused on worm locomotion, studying its characteristics as a function of the wave parameters, getting insights of its relation with velocity, stability, and consumption. One approach will be the use of genetic algorithms to find the optimal parameters of the wave, given an stability, velocity, and power consumption restriction. We also are planning to study locomotion in a plane, not restricted only to straight lines. Finally, a new generation of modules, with embeded FPGAs are being constructed.
Juan Gonzalez 2004-10-08