Control of dynamical systems gets considerably harder with an increasing number of control variables. Especially when the control variables are restricted to integer values, the solution is of combinatorial complexity. An example of such systems are Digital Hydraulic Drives, where several cylinders contribute to the output torque independently. In this work we present an optimal control approac...

accurate delivery of torque to implant screws is critical to generate ideal preload in the screw joint and to offer protection against screw loosening. mechanical torque-limiting devices (mtlds) are available for this reason. in this study, the accuracy of one type of friction-style and two types of spring-style mtlds at baseline, following fatigue conditions and sterilization processes were de...

− This paper gives details of a round robin torque comparison involving the National Physical Laboratory (NPL) and nine other UK laboratories. The comparison covered two ranges: 20 N·m to 100 N·m and 200 N·m to 1 kN·m. The work was an effective way of disseminating the unit of torque to industry via the UK’s new national torque standard, giving assurance to laboratories and customers and identi...

BACKGROUND The control of force and its between-trial variability are often taken as critical determinants of motor performance. Subjects performed isometric trunk flexion and extension forces without and with experiment pain to examine if pain yields changes in the control of trunk forces. The objective of this study is to determine if experimental low back pain modifies trunk isometric force ...

The most important geometric parameter in the friction stir welding (FSW) tool design is the shoulder diameter, which is currently estimated by trial and error. Here, we report a combined experimental and theoretical investigation on the influence of shoulder diameter on thermal cycles, peak temperatures, power requirements, and torque during FSW of AA7075-T6. An optimum tool shoulder diameter ...

This paper presents a new adaptive torque estimation algorithm for an interior permanent magnet synchronous motor (IPMSM) with parameter variations and cross-coupling between dand q-axis dynamics. All cross-coupled, time-varying, or uncertain terms that are not part of the nominal flux equations are included in two equivalent mutual inductances, which are described using the equivalent dand q-a...

A new approach to very accurate positioning of mechanical devices with nonlinear stick slip friction is presented in this paper The proposed controller applies narrow torque pulses to move a mechanism to a desired position despite nonlinear friction The pulse shapes generated by the controller are computed using a fuzzy logic approximation of the dependence between the desired displacement and ...