In this paper a simple terrain evaluation method for
hexapod robot is introduced. This method is based on feet coordinate
evaluation when all are on the ground. Depending on the feet
coordinate differences the local terrain evaluation is possible. Terrain
evaluation is necessary for right gait selection and/or body position
correction. For terrain roughness evaluation three planes are plotted:
two of them as definition points use opposite feet coordinates, third
coincides with the robot body plane. The leaning angle of body plane
is evaluated measuring gravity force using three-axis accelerometer.
Terrain roughness evaluation method is based on angle estimation
between normal vectors of these planes. Aim of this work is to
present a simple method for embedded robot controller, allowing to
find the best further movement settings.
 U. Saranli, M. Buehler, D. E. Koditschek. "Design, Modeling and
Preliminary Control of a Compliant Hexapod Robot" in Proceedings of
the 2000 IEEE Conference on Robotics & Automation, April 2000,
 E. Burkus, P. Odry. "Autonomous Hexapod Walker Robot "Szabad(ka)"
in Acta Polytechnica Hungarica vol. 5, no. 1, pp. 69-85, 2008.
 T. Luneckas, D. Udris. "Optimization of Hexapod Robot Locomotion"
in Electrical and Control Technologies, Kaunas, Technologija, 2009, pp.
 M. Castelnovi, R. Arkin, T. R. Collins. "Reactive Speed Control System
Based on Terrain Roughness Detection" in Proceedings of 2005 IEEE
Intl. Conference on Robotics and Automation (ICRA), pp. 891-896.
 R. Hoffman, E. Krotkov. "Terrain Roughnes Measurement from
Elevation Maps" in SPIE vol 1195 Mobile Robols IV, pp. 104-114,
 M. K. Shepard, B. A. Campbell, M. H. Bulmer, T. G. Farr, L. R. Gaddis,
J. J. Plaut. "The Roughness of Natural Terrain - A Planetary and
Remote Sensing Perspective" in Journal of Geophysical Research, vol.
106, no. E12, pp. 32,777-32,795, 2001.