INTRODUCTION Whereas deficits in muscle function, particularly power production, develop in old age and are risk factors for mobility impairment, a complete understanding of muscle fatigue during dynamic contractions is lacking. We tested hypotheses related to torque-producing capacity, fatigue resistance, and variability of torque production during repeated maximal contractions in healthy olde...

Switched reluctance motor drive system has greatly practical value in electric vehicle applications. For the characteristics of switched reluctance motor and electric vehicle application requirements, how to reduce the torque ripple effectively and ensure its average output torque, all these become a hot spot of research. Based on this, first of all, the nonlinear model of switched reluctance m...

Magnetization dynamics symmetry plays important roles in magnetization switching. Here we study magnetic field and spin torque induced magnetization switching. Spin moment transferring from polarized itinerant electrons to local magnetization provides a magnetization switching mechanism without using external magnetic field. Besides its importance in fundamental magnetization switching dynamics...

This paper presents an advanced torque ripple minimization method of a switched reluctance motor (SRM) using torque sharing function (TSF). Generally, TSF is applied into the torque control. However, the conventional TSF cannot follow the expected torque well because of the nonlinear characteristics of the SRM. Moreover, the tail current that is generated at a high speed motor drive makes unexp...

The open-loop torque control of synchronous motors with minimum torque ripple and minimum copper losses is presented. The control problem is viewed as an optimization problem for the nonlinear mapping from desired torque and position to the motor's phase currents. The performance of the controller to produce virtually ripple-free torque and to enhance the precision of position tracking is demon...

This study focuses on neuromuscular mechanisms behind ankle torque and EMG variability during a maintained isometric plantar flexion contraction. Experimentally obtained torque standard deviation (SD) and soleus, medial gastrocnemius, and lateral gastrocnemius EMG envelope mean and SD increased with mean torque for a wide range of torque levels. Computer simulations were performed on a biophysi...

The torque felt by a non-accreting protoplanet on a circular orbit embedded in a uniform surface density protoplanetary disk is analyzed by means of time-dependent numerical simulations. Varying the viscosity enables one to disentangle the Lindblad torque (which is independent of viscosity) from the corotation torque, which saturates at low viscosity and is unsaturated at high viscosity. The de...

Magnetorheological (MR) actuators provide controlled torque through control of an applied magnetic field. Therefore knowledge of the relationship between the applied current and output torque is required. This paper presents a new nonlinear modeling of MR actuators considering magnetic hysteresis to determine the torque-current nonlinear relationship. Equations for transmitted torque are derive...

This work focuses on the development of a wearable power-assisted orthosis for nursing care as a health care device to reduce the physical burden on carers. The most important aspect of developing a power-assisted orthosis is that it reflects the orthosis wearer’s intentions, coordinating with the wearer’s voluntary movements. To realize this intention, our work focuses on a torque around a cub...