Modeling of Motorized Orthosis Control

Abstract

Orthotic devices are defined as externally applied devices that are used to modify the structural and functional characteristics of the neuro-muscular and skeletal systems. The aim of the current study is to improve the control and movement of a robotic arm orthosis by means of an intelligent optimization system. Firstly, the control problem settlement is defined with the muscle, brain, and arm model. Subsequently, the optimization control, which based on a differential evolution algorithm, is developed to calculate the optimum gain values. Additionally, a cost function is defined in order to control and minimize the effort that is made by the subject and to assure that the algorithm follows as close as possible the defined setpoint value. The results show that, with the optimization algorithm, the necessary development force of the muscles is close to zero and the neural excitation level of biceps and triceps signal values are getting lower with a gain increase. Furthermore, the necessary development force of the biceps muscle to overcome a load added to the orthosis control system is practically the half of the one that is necessary without the optimization algorithm.

Automatic Identification Algorithm of Equivalent Electrochemical Circuit Based on Electroscopic Impedance Data for a Lead Acid Battery

“…As is the case with Particle Swarm Optimization (PSO), DE is a noncomplex but powerful population-based stochastic search technique. As presented in Aramendia et al [28], different agent sets are proposed by DE, and all agents follow the same procedure to improve the resulting agent set, evaluation, crossing, mutation, and selection. The three main vectors are described as follows:…”

Special Issue on “Human Health Engineering”

“…Contributions can focus on sensors, wearable hardware, algorithms, or integrated monitoring systems. We organized the different papers according to their contributions to the main parts of the monitoring and control engineering scheme applied to human health applications, namely papers focusing on measuring/sensing of physiological variables [24][25][26][27][28][29][30][31], contributions describing research on the modelling of biological signals [32][33][34][35][36][37][38], papers highlighting health monitoring applications [39][40][41][42], and finally examples of control applications for human health [43][44][45][46][47][48]. In comparison to biomedical engineering, we envision that the field of human health engineering also covers applications on healthy humans (e.g., sports, sleep, and stress) and thus not only contributes to develop technology for curing patients or supporting chronically ill people, but also for disease prevention and optimizing human well-being more generally.…”

“…The device they developed, aimed at assisting walking during the gait stance phase of people suffering from abnormal gaits, such as weak ankle, spasticity or foot drop, conditions that typically result after stroke. Whereas the previous three studies focused on control applications for assisting/improving walking behaviour, the work of Aramendia et al [47] studied a robotic arm orthosis to assist arm movements. The authors developed a numerical model of a muscle, arm, and orthosis and used this model for simulating different scenarios.…”