Omni-drive systems operate by having individual wheels apply torque in one direction in the same way as a regular wheel, but are able to slide freely in another direction (often perpendicular to the torque vector). The key advantage of omni-drive systems is that translational and rotational motion are decoupled for simple motion. However, in considering the fastest possible motion this is not n...

Herein, a new torsional device based on shape memory alloy elements and operating as torque limiter is presented. It consists of set pseudoelastic NiTi tapes working in series configuration. The are assembled radially with respect to the rotational direction work sequentially beam‐like bending mode. trend resulting may span from pulsating continuous by changing number tapes. Furthermore, use ma...

This paper proposes a new concept for attitude actuation for small satellites that uses active magnetic bearings to support and tilt a spinning rotor to provide 3-axis attitude control of the satellite using a single actuator. A controlled 3D motion in the spinning rotor provides a conventional torque output about the momentum axis and a gyroscopic torque output about any direction in the plane...

Harmonic force and torque, which are caused by rotor imbalance and sensor runout, are the dominant disturbances in active magnetic bearing (AMB) systems. To eliminate the harmonic force and torque, a novel control method based on repetitive control and notch filters is proposed. Firstly, the dynamics of a four radial degrees of freedom AMB system is described, and the AMB model can be described...

Detailed understanding of the action of biological molecular machines must overcome the challenge of gaining a clear knowledge of the corresponding free-energy landscape. An example for this is the elucidation of the nature of converting chemical energy to torque and work in the rotary molecular motor of F1-ATPase. A major part of the challenge involves understanding the rotary-chemical couplin...

We systematically investigated the effect of body rotation on the aerodynamic torque generation on flapping wings during fast turning maneuvers (body saccades) in the fruit fly Drosophila. A quasi-steady aerodynamic simulation of turning maneuvers with symmetrically flapping wings showed that body rotation causes a substantial aerodynamic counter-torque, known as flapping counter-torque (FCT), ...

BACKGROUND Fractured connections between implants and implant abutments or abutment screws are frequently encountered in a clinical setting. The purpose of this study was to investigate fracture strength using a torsion test at the interface between the implant and the abutment. METHODS Thirty screw-type implant with diameters of 3.3, 3.8, 4.3, 5.0, and 6.0 mm were submitted to a torsion test...

Grasp stability of a precision grip requires fine control of three-dimensional fingertip forces. This chapter begins with a review of the literature on how precision grip forces are affected by intrinsic object properties, anticipation, load direction, and sensory feedback. Previous studies have established that reactive, initial increases in grip forces (pulse-like ‘‘catch-up responses’’ in gr...

This paper presents a novel testbed capable of rotating a target to follow an arbitrary prescribed rotational trajectory, such as the tumbling motion of a satellite undergoing torque-free dynamics. This work is part of a larger research endeavor investigating technology applicable to autonomous rendezvous and docking with a tumbling satellite. This testbed provides unoccluded visibility of the ...

Orientational order of surfactant micelles and proteins on crystalline templates has been observed but, given that the template unit cell is significantly smaller than the characteristic size of the adsorbate, this order cannot be attributed to lattice epitaxy. We interpret the template-directed orientation of rodlike molecular assemblies as arising from anisotropic van der Waals interactions b...