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This contribution is concerned with joint angle calculation based on inertial measurement data in the context of human motion analysis. Unlike most robotic devices, the human body lacks even surfaces and right angles. Therefore, we focus on methods that avoid assuming certain orientations in which the sensors are mounted with respect to the body segments.(More)
We consider 6d inertial measurement units (IMU) attached to rigid bodies, e.g. human limb segments or links of a robotic manipulator, which are connected by hinge joints and spheroidal joints. Novel methods for joint axis estimation and joint position estimation are presented that exploit the kinematic constraints induced by these two types of joints. The(More)
A typical application of Iterative Learning Control (ILC), namely trajectory tracking on a lab-scale gantry crane, is considered. However, the load is only allowed to move in the close proximity of the reference trajectory. Since these output constraints lead to disrupted trials, the pass length in this ILC system is not constant. In this contribution, we(More)
The limited ability to dorsiflex the foot, known as drop foot, can be treated by functional electrical stimulation. Therein, undesired foot eversion/inversion is a common problem which is usually corrected by tedious manual repositioning of the electrodes. We address this issue by presenting a feedback-control solution featuring three major contributions:(More)
We propose a consensus-based distributed voltage control (DVC), which solves the problem of reactive power sharing in autonomous meshed inverter-based microgrids with inductive power lines. Opposed to other control strategies available thus far, the DVC does guarantee reactive power sharing in steady-state while only requiring distributed communication(More)
Due to their relative ease of handling and low cost, inertial measurement unit (IMU)-based joint angle measurements are used for a widespread range of applications. These include sports performance, gait analysis, and rehabilitation (e.g., Parkinson's disease monitoring or poststroke assessment). However, a major downside of current algorithms,(More)
This contribution is concerned with the design and control of a novel drop foot stimulator. Unlike almost all other drop foot stimulators, the present device uses a combination of gyroscopes and accelerometers attached to the foot, and optionally to the shank. On the one hand, the inertial sensor on the foot is used for a detailed gait phase detection which(More)
Functional Electrical Stimulation via electrode arrays enables the user to form virtual electrodes (VEs) of dynamic shape, size, and position. We developed a feedback-control-assisted manual search strategy which allows the therapist to conveniently and continuously modify VEs to find a good stimulation area. This works for applications in which the desired(More)
Rehabilitation after stroke can be improved by EMG­proportional FES. While the muscle is being stimulated proportional to its detected residual voluntary activation, the patient practices to reach pre­defined joint angles iteratively. Often the patient has bad control over the movement and oscillations occur. A potential reason is the nonlinear static(More)