Many people suffer from disability, caused by arm amputees and congenital disorder of the musculoskeletal system. An upper limb prosthesis can help disabled people to do their usual life activity. The aim of the paper is to develop upper limb prosthetic device controlled by myoelectric signals. At present the most complicated problem in upper limb prosthetics is connected with processing of neuromuscular signals for their use in control of the prosthesis. In modern prosthesis the intensity of muscle activity is extracted from the electromyographic signals. Prosthetic devices should ideally compensate for the loss of fine, coordinated movements of the hand, provide proprioceptive feedback, and have an esthetic exterior. From this point of view, identification of single finger movements seems very attractive. On the one hand it allows to restore functionality of amputated limb close to the healthy one. On the other hand existing results in the field of multifinger control require complicated computations. This leads to cost increase of the end-user device. To overcome this problem, we propose amplitude-based window recognition method with low computational complexity. The proposed solution can be implemented in real-time control using low cost Arduino nano microcontroller. A prototype of prosthetic hand with novel engineering solutions and proposed software is suggested. Experimental and statistical validation of identification scheme on a group of healthy people is considered. The proposed solution is tested in real time in autonomous mode. Experimental results for disabled man is provided. A discussion of the obtained results is given.