Nanotechnology involves the ability to see and control individual atoms and molecules which are about 100 nanometer or smaller. One of the major tools used in this field is atomic force microscopy which uses a wealth of techniques to measure the topography and investigates the surface forces in nanoscale. Friction force is the representation of the surface interaction between two surfaces an...

Force intermittency is one of the major causes of motor variability. Focusing on the dynamics of force intermittency, this study was undertaken to investigate how force trajectory is fine-tuned for static and dynamic force-tracking of a comparable physical load. Twenty-two healthy adults performed two unilateral resistance protocols (static force-tracking at 75% maximal effort and dynamic force...

We explored possible effects of negative covariation among finger forces in multifinger accurate force production tasks on the classical Fitts's speed-accuracy trade-off. Healthy subjects performed cyclic force changes between pairs of targets "as quickly and accurately as possible." Tasks with two force amplitudes and six ratios of force amplitude to target size were performed by each of the f...

Cardiac catheters allow physicians to access the inside of the heart and perform therapeutic interventions without stopping the heart or opening the chest. However, conventional manual and actuated cardiac catheters are currently unable to precisely track and manipulate the intracardiac tissue structures because of the fast tissue motion and potential for applying damaging forces. This paper ad...

Studies of fingertip force production have shown that self-produced forces are perceived as weaker than externally generated forces. This is due to mechanisms of sensory reafference where the comparison between predicted and actual sensory feedback results in attenuated perceptions of self-generated forces. Without an external reference to calibrate attenuated performance judgments, a compensat...

The purpose of the study was to examine the effect of prolonged vibration on the force fluctuations during a force-matching task performed at low-force levels. Fourteen young healthy men performed a submaximal force-matching task of isometric plantar flexion before and after Achilles tendon vibration (n = 8, vibration subjects) or lying without vibration (n = 6, control subjects) for 30 min. Th...

PURPOSE This study examined the ability of 10 young (25.3 +/- 2.8 yr) healthy individuals to control knee-extension force during several discrete concentric and eccentric contractions. METHODS Subjects performed maximal and submaximal tasks on a KIN-COM isokinetic dynamometer. The submaximal tasks were to match a force-time parabola with a time to peak force of 200 ms at five target-forces (5...