Formal description techniques in robot programming

A study is reported whose aim was to produce a system to facilitate offline programming of robots and to provide a testbed for alternative algorithms for the services provided. The system was specified using the formal description technique LOTOS (language of temporal ordering specification). LOTOS is best known for its use in the description of OSI protocols and is supported by an ISO standard. LOTOS consists of a process algebra for specifying the structure of the system and the interactions between components of the system, and an algebraic data typing mechanism for specifying the operations the system carries out. The description of the system was heavily influenced by techniques used in the design of operating systems. Concurrency was introduced at the initial design stage, there was an explicit separation of concerns and the specification was structured hierarchically, with actions at one level appearing atomic to the next higher level. Each level in the hierarchy provides an increasingly abstract view of the robot. The resulting description was executed, or animated, using the SEDOS tool, to help determine that the correct behaviour had been encapsulated by the description. The specification was then implemented on a network of transputers, using 3L Parallel Pascal.