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...

We examined subjects’ perceptions of physical effort in the presence of feedback distortion as they were asked to resist forces produced by a haptic device. Subjects pressed against a simulated spring with the index finger until they reached a target force, which they held for a designated time duration. Visual feedback of the target force level and the designated time duration was provided. On...

The purpose of this study was to compare the discharge characteristics of motor units recruited during an isometric contraction that was sustained with the elbow flexor muscles by older adults at target forces that were less than the recruitment threshold force of each isolated motor unit. The discharge times of 27 single motor units were recorded from the biceps brachii in 11 old adults (78.8 ...

In this article, we explore the effect of the occurrence of a target sound on the force that is applied by the ear when listening at a surface because differences in applied force induce variation in carprints of a single ear. Forty two subjects each listened four times at a surface. During two of these listening efforts there was silence. While the subjects were listening, we measured the amou...

We study theoretically and by means of molecular dynamics (MD) simulations the generation of mechanical force by grafted polyelectrolytes in an external electric field, which favors its adsorption on the grafting plane. The force arises in deformable bodies linked to the free end of the chain. Varying the field, one controls the length of the nonadsorbed part of the chain and hence the deformat...

A multi-modal mouse incorporating tactile and force feedback was tested in a target selection task with 12 subjects . Four feedback conditions (normal , tactile , force , tactile 1 force) were combined with three target distances and three target sizes . We found significant reductions in the overall movement times and in the time to stop the cursor after entering the target . This ef fect was ...

Previous research suggests that removal of visual feedback of force output in a sequential force production task results in a continuous escalation of the force magnitudes produced. Central predictive mechanisms involving reafference result in self-generated forces being perceived as weaker, thus leading to a systematic over-production of force. While this effect has been widely examined with r...