A HARDWARE-BASED IMPLEMENTATION OF A TSK FUZZY CONTROLLER FOR A WHEELCHAIR SYSTEM

Controllers of all sorts have been applied recently for dealing with smooth and smart navigation of wheelchair system. Stringent requirements are being made by designers and users of these systems, especially over the past few years, where the population of elderly and those seeking quality health care has increased. Among powerful controllers proposed are those based on fuzzy logic systems. But optimal design and hardware implementation challenges have been among the challenging issues to use these systems in mass application. We present here different aspects for designing, implementing and optimizing a fuzzy logic controller (FLC) for wheelchair navigation system, using a field-programmable gate array (FPGA). The main goal of this work is the hardware implementation with focus on FPGA resources optimization. In fact, this optimization is necessary to limit the FPGA hardware resources. For this purpose, we performed software and hardware optimization procedures. The software procedure is performed using Matlab Anfis environment to reduce the number of rules and to optimize the membership functions shapes. The hardware procedure is performed using FPGA to limit the resources of the divider block needed to compute the FLC output. For the latter optimization approach, the FLC is implemented in VHDL language, synthesized, optimized, placed and routed, and simulated with specific FPGA board. Basically two FLC controllers are designed and then compared in terms of their hardware resources and frequency. Both simulation results are presented for various targets.