Experiences with the subsumption architecture

A subsumption architecture has been proposed as an effective approach for the construction of robust, real-time control systems for mobile robots. To investigate its strengths and weaknesses, a simulation of the architecture was developed called the Subsumption Architecture Tool (SAT). This simulation allows various models of system behavior to be quickly built and tested. During the building and testing of the SAT, issues related to some architectural features became evident: level of commitment of each layer; code redundancy; problem decomposition and programming style; complexity of large system; and abstract reasoning capabilities. The effects of these issues are presented with respect to the design and implementation choices of two sample layers of behavior. These layers are used to illustrate considerations that need to be taken into account when a project team is considering the use of the subsumption architecture or when a subsumption-architecture-based system is being designed and implemented