In the original paper "living machines" from 1995, two types of robots were introduced which was the Walkman (a simple crawler) and Spyder, which is a more elaborated legged robot.
It has robot legs and can move forward on the carpet but the legs don't have dedicated joints for articulated movements.
Sometimes, crawling robots are equipped with dedicated microcontrollers plus a radio controlled chipset[2] while in other implementations a minimalist approach is used.
A possible alternative control over teleoperation is a nv network which is a specialized form of a central pattern generator.
[4] This is a pseudorandom number generator which is producing an oscillating signal.