Photons carry linear momentum and spin angular momentum when circularly or elliptically polarized. During light-matter interaction, transfer of linear momentum leads to optical forces, whereas transfer of angular momentum induces optical torque. Optical forces including radiation pressure and gradient forces have long been used in optical tweezers and laser cooling. In nanophotonic devices, opt...

in conventional direct torque control (dtc), the stator flux is usually kept constant by controlling the x-axis component of the stator voltage in the stator flux reference frame. the torque is then controlled by the y-axis component of stator voltage. in this scenario, the stator current does not exceed its permissible value. however, in the so-called optimal efficiency mode, the induction mot...

torque, speed, and power as mechanical variables are associated with the functional performance of any rotating machinery. the real-time performance and the efficiency of a machine can be determined with on-line measurement of these parameters. in this investigation a rotary torque meter (transducer) was constructed from strain gauge sensors for measuring the torque of rotating shafts. the syst...

Purpose Friction-style and spring-style torque wrenches are used to tighten implant abutments and prosthetic screws. The mechanical stability of these torque wrenches is crucial for the implant-abutment connection. The purposes of this study were to assess the performance of five brands (Straumann, Zimmer, Implant KA, Bredent, and Biohorizons) of wrench and to evaluate possible changes in appli...

We present an entirely novel, self-limiting photolithography mechanism in off-stoichiometry thiol-ene (OSTE) polymers enabling high-resolution and high-aspect ratio features. The OSTE polymers have previously been shown to be promising materials for fabrication of microfluidic devices with tailored surface modifications and mechanical properties. We here introduce direct lithography for micropa...

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 ...

Two novel devices, torsional actuator and torsional stepper motor, are described and their performance is investigated in detail. Both devices were designed to produce large angular displacement and large torque output from the piezoelectric d15 shear response. In the torsional actuator, the large displacement can be achieved due to built-in amplification of piezoelectric strain using the aspec...

This paper presents a new design of a harness for torso force application in locomotion interfaces. This mechanical coupling between a user’s body and the force feedback device is a key aspect for the effective exploitation of this class of devices. Issues of compliance, backlash, force distribution, and comfort have been considered in the new design. Experimental results show that subjects adj...

A low-temperature process for mass-parallel self-assembly of three-dimensional micro-opto-electro-mechanical systems is described. The devices are fabricated by dry etching of bonded silicon-on-insulator wafers, and selfassembled by out-of plane rotation powered by a surface tension torque obtained by melting thick pads of photoresist. Fixed optical mirrors oriented at 45û and 90û to the substr...

The technique of electrorotation was used to apply torque to cells of the bacterium Escherichia coli tethered to glass coverslips by single flagella. Cells were made to rotate backward, that is, in the direction opposite to the rotation driven by the flagellar motor itself. The torque generated by the motor under these conditions was estimated using an analysis that explicitly considers the ang...