Actually, wheelchair users with impairment or total lost of movements in arms or hands have many difficult to operate conventional motorized wheelchair. This project develop and integrate support systems having focus in a friendly user interface, like voice recognition, filters in joysticks, sonar for collision avoidance and motor drivers, all integrated by a hierarchic control architecture. Voice recognition was developed in two different architectures and implementations methods: the first by using commercial voice recognition software and the second by a microcontroller firmware, allowing a significant cost and weight reduction. For wheelchair user with hands or arms impairment like repetitive strain injuries or muscular dystrophy a joystick filter must to be used to interpret the movements where oscillate around a desired position. Since different kinds of interfaces and inputs are used, a consistent integration is necessary between them. The integration system uses a hierarchical logic, meaning that are some inputs are predominant than others when used, and stays in an idle condition until an event occurs. Hierarchical logic can be used for input management or obstacle avoidance, when an unsafe command is performed, like to drive to close of a wall, when the navigation system will disable some movement's directions. To evaluate this project, a prototype was built in reduced scale, but conserving all sensors and navigation architecture characteristics. Copyright © 2007 SAE International. Bourhis, G., Agostini, Y., The Vahm Robotized Wheelchair: System Architecture and Human-Machine Interaction (1998) Journal of Intelligent and Robotic Systems: Theory and Applications, 22 (1), pp. 39-50Shaw, R., Crisman, E., Loomis, A., Laszewski, Z., The eye wink control interface: Using the Computer to Provide the Severely Disabled with Increased Flexibility and Comfort (1990) IEEE, pp. 105-111. , http://ieeexplore.ieee.org/iel2/483/3324/00109386.pdf?arnumber=109386, on-line, available inLaw, C.K.H., Leung, M.Y.Y., Xu, Y., Tso, S.K., A cap as interface for wheelchair control (2002) IEEE International Conference on Intelligent Robots and Systems, 2, pp. 1439-1444Min, J.W., Kyoobin, L., Lim, S.C., Kwon, D.S., Human-friendly interfaces of wheelchair robotic system for handicapped persons (2002) IEEE/RSJ Out, pp. 1505-1510. , http://ieeexplore.ieee.org/iel5/8071/22356/01043968.pdf, on-line, available in. Access 23 AprJacob, R.J.K., The Use of Eye Movements in Human-Computer Interaction Techniques:What You Look at Is What You Get (1991) ACM Transactions on Information, pp. 152-169Yanco, H.A., Wheelesley: A Robotic Wheelchair System: Indoor Navigation and User Interface (1998) Assistive Technology and AI, pp. 256-268. , http://www.cs.uml.edu/~holly/papers/ai-at-yanco.pdf, on-line, available inTaylor, P.B., Nguyen, H.T., Performance of a Head-Movement Interface for Wheelchair Control (2003) IEEE EMBS, Set, pp. 1590-1593. , http://ieeexplore.ieee.org/iel5/9009/28599/01279669.pdf, on-line, available inGips, J., (1998) On Building Intelligence into EagleEyes, pp. 50-58. , http://www.springerlink.com/index/LLC1PMYUCQ4NHVTJ.pdf, Computer Science Department Boston College Chestnut Hill, on-line, available in. Access 18 Apr. 2007Yanco, H.A., Gips, J., Preliminary Investigation of a Semi-Autonomous Robotic Wheelchair Directed Through Electrodes (1997) Proceedings of the Rehabilition Engineering Society of North America Annual Conference, pp. 414-416. , http://www.cs.uml.edu/~holly/papers/yanco-gips-esna97.pdf, Jun. on-line, available inBourhis, G., Agostini, Y., Man-machine Cooperation for the Control of an Intelligent Powered Wheelchair (1998) Journal of Intelligent and Robotic Systems: Theory and Applications, 22 (3-4), pp. 269-287Rasmussen Jens, Skills, rules and knowledgesignals, signs and symbols, and other distinctions in human performance models (1983) IEEE Transactions on Systems, Man and Cybernetics, SMC-13 (3), pp. 257-266Keates, S., Clarkson, P.J., Robinson, P., (2007) Developing A Methodology for the Design of Accessible Interfaces, , http://ui4all.ics.forth.gr/UI4ALL-98/keates.pdf, online,- available in. Access 23 mayEngdahl, T., (2000) Powering Microphones, , http://www.epanorama.net/circuits/microphone_powering.html, 5 December 2007