Digital angular-displacement transducer with iterative error correction

1995 ◽  
Vol 38 (5) ◽  
pp. 502-506
Author(s):  
A. M. Shekikhanov ◽  
V. B. Ibragimov
Keyword(s):  
Error Correction ◽  
Angular Displacement ◽  
Displacement Transducer ◽  
Iterative Error

Improved measurement accuracy from iterative error correction

1981 ◽  
Vol 24 (4) ◽  
pp. 262-264
Author(s):  
T. M. Aliev ◽  
D. I. Damirov ◽  
A. M. Shekikhanov
Keyword(s):  
Error Correction ◽  
Measurement Accuracy ◽  
Iterative Error

A Device for Measuring Relative Angular Displacement

1998 ◽  
Vol 120 (2) ◽  
pp. 299-302 ◽  
Author(s):  
R. P. McCabe ◽  
S. S. Kohles ◽  
S. V. Chelikani ◽  
R. Vanderby
Keyword(s):  
Angular Displacement ◽  
Kinematic Chain ◽  
Displacement Transducer ◽  
Open Loop ◽  
Rotational Displacement

A simple, inexpensive, and accurate way to measure relative segmental rotations resulting from torsional loadings locally is described. To measure these rotations, we fabricated a planar spatial linkage (open-loop kinematic chain) requiring only one rotational displacement transducer. This paper describes this device, defines its kinematics, and examines its accuracy.

Comparison of the contractile responses to irregular and regular trains of stimuli during microstimulation of single human motor axons

2014 ◽  
Vol 111 (7) ◽  
pp. 1499-1506 ◽  
Author(s):  
Michael Leitch ◽  
Vaughan G. Macefield
Keyword(s):  
Angular Displacement ◽  
Motor Units ◽  
Common Peroneal Nerve ◽  
Displacement Transducer ◽  
Motor Axons ◽  
Interspike Intervals ◽  
Contractile Responses ◽  
Single Motor ◽  
Single Motor Units ◽  
Voluntary Contractions

During voluntary contractions, human motoneurons discharge with a physiological variability of ∼20%. However, studies that have measured the contractile responses to microstimulation of single motor axons have used regular trains of stimuli with no variability. We tested the hypothesis that irregular (physiological) trains of stimuli produce greater contractile responses than regular (nonphysiological) trains of identical mean frequency but zero variability. High-impedance tungsten microelectrodes were inserted into the common peroneal nerve and guided into fascicles supplying a toe extensor muscle. Selective microstimulation was achieved for 14 single motor axons. Contractile responses were measured via an angular displacement transducer over the relevant toe. After the responses to regular trains of 10 stimuli extending from 2 to 100 Hz were recorded, irregular trains of 10 stimuli, based on the interspike intervals recorded from single motor units during voluntary contractions, were delivered. Finally, the stimulation sequences were repeated following a 2-min period of continuous stimulation at 10 Hz to induce muscle fatigue. Regular trains of stimuli generated a sigmoidal increase in displacement with frequency, whereas irregular trains, emulating the firing of volitionally driven motoneurons, displayed significantly greater responses over the same frequency range (8–24 Hz). This was maintained even in the presence of fatigue. We conclude that physiological discharge variability, which incorporates short and long interspike intervals, offers an advantage to the neuromuscular system by allowing motor units to operate on a higher level of the contraction-frequency curve and taking advantage of catch-like properties in skeletal muscle.

Sign in / Sign up

Export Citation Format

Share Document