Makita Hapiy 2.0: Design and Development of a Low-Cost and Lightweight Myoelectric Transradial Prosthesis using 3D...

In this study, a low-cost and lightweight transradial myoelectric prosthesis was developed. 3D printing with materials such as polylactic acid (PLA) and thermoplastic polyurethane (TPU) was employed, along with an electromyography (EMG) sensor to condition the electromyographic signal. A Butterworth band-pass filter was applied to remove residual noise, followed by an exponential moving average (EMA) filter with a smoothing constant of 0.015 to calculate the envelope. Subsequently, the squared envelope was calculated to estimate the signal energy, which facilitated peak detection. The latter was used by the Arduino Nano to control a servo and two Pololu geared motors, which were configured by a 4-state switch for the user to select the grip type as needed: precision, hook, spherical or cylindrical. The prosthesis is considered viable due to its structurally robust mechanical design tested under stress situations, low cost of $43, light weight of 0,460 kg and its ability to offer various grips through optimal control of the EMG signal, making it promising to improve the quality of life of people with amputations and limited economic resources.Clinical Relevance-Makita Hapiy 2.0 is presented as an affordable and lightweight transradial myoelectric prosthesis prototype, which reduces its price by "90%" compared to other rehabilitation devices in research and on the market.