Using LEGO Mindstorm NXT, I developed this 6 legged robot that can walk both forwards and backwards. The turning is by pivot motion at the front and back. a video can be found Ekho Crawl . I've been interested in walking robots for sometime. As seen in the final picture, the programing is quite simple making Ekho turn about 90 degrees right when within 15 cm of a flat surface using the Ultra Sonic Sensor.