Spastic cerebral palsy is a disease that causes stiffness in the muscles, producing difficulty in the movement of the impaired regions of the body, leading to dependence and psychological damage. Moreover, in order to improve the quality of life of these patients arises the proposal of using medical robots as assistive devices to help them in their Basic Activities of Daily Living (BADL). Therefore, this research consists of a novel design and simulation of anthropomorphic 4 DOF (Degrees of Freedom) robotic arm, mounted on electric wheelchair controlled by a joystick. The development of this medical device was performed in the Mechatronics Laboratory at Ricardo Palma University in Peru during the period of 2016 to 2018, with the aim of finding an effective solution for the assistance of people with a limited range of movement caused by cerebral palsy. The mechanical, electrical and electronic components were designed using CAD software, considering the dynamic mechanism, weight lifted, and features of the patients with this disease. Also, the structure of the model was validated using the finite element method and the actuators were selected applying motion study analysis. Finally, the results of the simulation showed a successful and functional design, concluding that this biomechatronic design achieves an improvement in the quality of life of the patient. Besides, its assembly implementation is expected to be ready by 2021.