Crawler (BEAM)

{{Short description|Type of robot}}

In BEAM robotics, a crawler is a robot that has a mode of locomotion by tracks or by transferring the robot's body on limbs or appendages. These do not drag parts of their body on the ground.

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.{{cite journal |doi=10.1016/0921-8890(95)00019-c |year=1995 |publisher=Elsevier BV |volume=15 |number=1–2 |pages=143–169 |author=Brosl Hasslacher and Mark W. Tilden |title=Living machines |journal=Robotics and Autonomous Systems }} The difference between a walker and a crawler is, that the crawler is more primitive. It has robot legs and can move forward on the carpet but the legs don't have dedicated joints for articulated movements. Instead they are mounted directly on the robot's base.

The design of a crawler robot isn't specified in detail and each robot engineer is allowed to build their own version. Sometimes, crawling robots are equipped with dedicated microcontrollers plus a radio controlled chipset{{cite conference |doi=10.1109/secon.2010.5453839 |year=2010 |publisher=IEEE |author=Adam Harris and James M. Conrad |title=Hybrid control of a simple walking autonomous robot |conference=Proceedings of the IEEE SoutheastCon 2010 (SoutheastCon) }} while in other implementations a minimalist approach is used.{{cite tech report |title=A Minimalist Approach to Design of Walking Robots |author=Moses, Matthew S |year=2000 |institution=Sandia National Labs., Albuquerque, NM (US); Sandia National Labs }} What all these robots have in common is, that they are following the philosophy of Biology, Electronics, Aesthetics and Mechanics which is about imitating biological bugs.

A possible alternative control over teleoperation is a nv network which is a specialized form of a central pattern generator.{{cite journal |title=A Comparison of Several Hardware-Realized Central Pattern Generators (CPGs) |author=Wu, Dongrui and Tan, Woei Wan and Vadakkepat, Prahlad |journal=Advanced Control Technology Laboratory, National University of Singapore |year=2005 }} This is a pseudorandom number generator which is producing an oscillating signal. It moves the legs similar to a clockwork.