Fine Motor Control with CBR Protective Gloves

1987 ◽  
Vol 31 (11) ◽  
pp. 1206-1210 ◽  
Author(s):  
Demetrios Karis
Keyword(s):  
Motor Control ◽  
Coefficient Of Friction ◽  
Ring Finger ◽  
Fine Motor ◽  
Control Task ◽  
Trial Time ◽  
Cursor Control ◽  
The Coefficient Of Friction ◽  
Within Subjects ◽  
The Difference

Using a within-subjects design, performance on a continuous cursor control task was measured in three conditions: no gloves, flight gloves, and a combination of three gloves worn simultaneously for chemical, biological, or radiological (CBR) protection. Twelve subjects used their left ring finger on a two-axis force controller to move a cursor on a CRT. After centering it over one of eight possible targets, they depressed the controller to designate the target and end a trial. Time to acquire the target and accuracy in centering the cursor over the target were recorded. Subjects had faster acquisition times in the two glove conditions with no increase in errors, although only the difference between the CBR gloves and no-gloves was statistically significant. My explanation for these findings is that the thickness of the gloves may have improved the fit of the fingertip in the force controller, which was concave, and also prevented the finger from slipping by increasing the coefficient of friction between the finger and the controller.

Effect of surface structure, composition and texture on friction under boundary conditions

1952 ◽  
Vol 212 (1111) ◽  
pp. 508-512
Keyword(s):  
Oxide Film ◽  
Boundary Conditions ◽  
Coefficient Of Friction ◽  
Substrate Material ◽  
Pure Aluminium ◽  
Surface Layers ◽  
The Coefficient Of Friction ◽  
The Difference ◽  
Frictional Behaviour ◽  
Effect Of Surface

The coefficient of friction of surfaces lubricated under boundary conditions may be profoundly affected by such factors as the degree of working of the substrate material, the nature of the oxide film and the degree of roughness of the surface. Experiments are described wherein the frictional behaviour of surfaces of stainless steel specimens prepared in various ways was compared. The worked surface layers in these particular experiments appear to increase the value of the coefficient of friction, but the effect of surface texture is of predominant importance. The effect of different oxide films is best illustrated by reference to pure aluminium, the surface of which has been oxidized under different environmental conditions. The constitution of the oxide film formed is modified with a consequent effect on boundary friction. When the friction of rough and smooth surfaces is compared, the difference in behaviour appears to be qualitative rather than quantitative.

Friction Characteristics of Porous Rubber Under Wet Conditions

2009 ◽  
Author(s):  
Yutaro Kosugi ◽  
Tomoaki Iwai ◽  
Yutaka Shokaku ◽  
Naoya Amino
Keyword(s):  
Friction Force ◽  
Coefficient Of Friction ◽  
Contact Surface ◽  
Road Surface ◽  
Water Removal ◽  
The Road ◽  
Rubber Specimen ◽  
The Coefficient Of Friction ◽  
The Difference ◽  
Tread Rubber

In recent years, porous rubber has been used as a tread matrix for studless tires. It is said that the pores in the tread rubber remove water between the tire and the wet road surface; however, the water removal is not sufficiently well understood. In this study, a rotating rubber specimen was rubbed against a mating prism to observe the contact surface. The friction force was also measured simultaneously with observation of contact surface. The water entering the pores was distinguished by the continuity method. As the result of these experiments, the coefficient of friction for rubber having pores on the surface was found to be larger than that of rubber without pores. Moreover, the difference in the coefficient of friction for rubber specimens with and without pores tended to be larger at lower sliding speeds. No water entered pores 3mm or less in diameter at any sliding speed in this experiment. An experiment to make the rubber specimen collide with the mating prism was conducted since actual tires seem to be deformed by the vehicle weight, such that the tire surface might contact the road collisionally. In the resulting collision experiment, the water did enter pores 3mm in diameter.

scholarly journals An Experimental Study of the Frictional Properties of Steel Sheets Using the Drawbead Simulator Test

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4037 ◽  
Author(s):  
Trzepiecinski ◽  
Kubit ◽  
Slota ◽  
Fejkiel
Keyword(s):  
Coefficient Of Friction ◽  
Extreme Values ◽  
Rolling Direction ◽  
Frictional Resistance ◽  
Friction Reduction ◽  
Experimental Investigations ◽  
Sheet Rolling ◽  
The Coefficient Of Friction ◽  
The Difference ◽  
Lubrication Conditions

This article presents the results of an experimental investigation of the frictional resistance arising in a drawbead during sheet metal forming. The frictional characterization of DC04 deep drawing quality steels commonly used in the automotive industry is carried out using a friction simulator. The effects of some parameters of the friction process on the value of the coefficient of friction have been considered in the experimental investigations. The friction tests have been conducted on different strip specimens, lubrication conditions, heights of drawbead and specimen orientations in relation to the sheet rolling direction. The results of drawbead simulator tests demonstrate the relationship that the value of the coefficient of friction of the test sheets without lubrication is higher than in the case of lubricated sheets. The lubricant reduces the coefficient of friction, but the effectiveness of its reduction depends on the drawbead height and lubrication conditions. Moreover, the effectiveness of the reduction of the coefficient of friction by the lubricant depends on the specimen orientation according to the sheet rolling direction. In the drawbead test, the specimens oriented along the rolling direction demonstrate a higher value of coefficient of friction when compared to the samples cut transverse to the rolling direction. The smaller the width of the specimen, the lower the coefficient of friction observed. The difference in the coefficient of friction for the extreme values of the widths of the specimens was about 0.03–0.05. The use of machine oil reduced the coefficient of friction by 0.02–0.03 over the whole range of drawbead heights. Heavy duty lubricant even reduced the frictional resistances by over 50% compared to dry friction conditions. The effectiveness of friction reduction by machine oil does not exceed 30%.

Analysis of the inertial propulsion concept

2020 ◽  
pp. 12-19
Author(s):  
A. A. Sabirzyanov ◽  
Keyword(s):  
Remote Control ◽  
Friction Force ◽  
Coefficient Of Friction ◽  
Average Velocity ◽  
Classical Mechanics ◽  
Average Speed ◽  
The Coefficient Of Friction ◽  
The Difference ◽  
The Right ◽  
Propulsion Concept

In this paper, an inertial device of the simplest design is proposed, which allows us to visually analyze the principle of its operation. The device is a radio-controlled car placed on the bottom of a long light cardboard box. The box is on the table. Using the remote control, the car accelerates and collides with one of the walls. On impact, the box moves across the table. Next, the car is taken to the opposite wall by the remote control without a collision. Then the process is repeated, as a result of which the device jerks along the table in one direction (in the example - to the right). The advantage of this method of control is that it is contactless, the disadvantage is that it is manual. In the framework of classical mechanics, the average speed of the box movement on the table is calculated. It depends on the ratio of the mass of the car and the box, the proportion of weight that falls on the driving wheels, the coefficient of friction between the wheels and the bottom of the box, the coefficient of friction between the box and the table, the difference in the length of the box and the car. It is shown that the average speed with a decrease in the friction force on the side of the support should first increase, and with a further decrease in friction - decrease. A condition is found under which the dependence of the average velocity on the friction force has a maximum.

scholarly journals Characteristics of a Tire Friction and Performances of a Braking in a High Speed Driving

2014 ◽  
Vol 6 ◽  
pp. 260428 ◽  
Author(s):  
Yumrak Oh ◽  
Hoguen Lee
Keyword(s):  
Coefficient Of Friction ◽  
High Speed ◽  
Skid Resistance ◽  
Conservation Of Energy ◽  
Driving Speed ◽  
The Coefficient Of Friction ◽  
Braking Distance ◽  
The Difference ◽  
Tire Friction ◽  
Safe Road

The goal of pavement is to deliver the fine roughness and the safe road surface to traffic. It requires a secured and comfortable surface using the controlled speed of road. Through adjusting driving speed, skid resistance can be altered in one of the performances of the pavement surface. In high speed driving, there might be a certain level of risk, not in the same level as the proposed roads. Hence, this study first analyzes the speed equation under a consideration of a braking distance and then suggests the friction coefficient in high speed driving with the principle of conservation of energy. If we accept simply that the coefficient of friction is independent of speed, the difference between analysis and test value for braking distance is greatly generated. Therefore we have to analyze the coefficient of friction as an exponential function of braking speed of a vehicle.

scholarly journals Effectiveness of current physiotherapy in carpal tunnel syndrome

2021 ◽  
Vol 5 (3) ◽  
pp. 87-89
Author(s):  
Ferhan Soyuer
Keyword(s):  
Motor Control ◽  
Carpal Tunnel Syndrome ◽  
Carpal Tunnel ◽  
Ring Finger ◽  
Fine Motor ◽  
Ultrasound Therapy ◽  
Study Results ◽  
Tunnel Syndrome ◽  
Nocturnal Awakening ◽  
Therapy Manual

Carpal Tunnel Syndrome (CTS) is a constellation of symptoms associated with compression of the median nerve at the wrist in the carpal tunnel. The main symptoms of CTS are numbness, pain and tingling of the first three fingers and radial side of the ring finger, nocturnal awakening is due to pain and impaired fine motor control because of weakness of the hand. Until now, the study results in which conservative methods have been applied in the treatment of CTS are contradictory. CTS rehabilitation includes laser therapy, ultrasound therapy, manual therapy, neurodynamic techniques, functional massage, splint, exercises etc. Alternative treatments for CTS include: acupuncture, massages, the Chinese cupping massage. The aim of this review is to explain the current physiotherapy methods applied in CTS patients and the research results on this subject.

A study of the microtopography of some surfaces by means of a friction technique

1964 ◽  
Vol 279 (1377) ◽  
pp. 161-169 ◽  
Keyword(s):  
Coefficient Of Friction ◽  
Plane Surface ◽  
Quantitative Index ◽  
Dimensionless Constant ◽  
Roughness Index ◽  
The Coefficient Of Friction ◽  
The Difference ◽  
Asperity Distribution ◽  
Surface Examination ◽  
Grain Diameter

A range of results has been obtained for a variety of surfaces by means of a friction tech­nique of surface examination in which elastically deforming surface asperities slide against a smooth incompressible plane surface. The effect of the size of the emery grain on the abrasion of sheets of Perspex was investigated in friction experiments using rubber negative replicas of the abraded surfaces. It was found that the roughness index γ/μ 2 where γ is a dimensionless constant and μ is the coefficient of friction was about 40 times as great for surfaces abraded with 40-grade emery cloth (average grain diameter 580 μ m) as for surfaces abraded with 00-grade emery (grain diameter 11 μ m). The variation of γ/μ 2 with load was also entirely different in these two extreme cases. For the smoother replica the asperities were nearly coplanar but for the rougher surface a marked asperity distribution in depth had occurred so that high loads were required to bring all the asperities into contact with the slider. It was found that the negative replicas were consistently rougher than the corresponding positive ones and reasons for this connected with the abrasion process have been suggested. The different results given by abraded steel and Perspex surfaces can be explained as due to the difference in hardness of the two materials. Turned surfaces have also been examined and the variation of γ/μ 2 with load found to be characteristic of the shape of the turning grooves in the surface, giving a result quite different from that obtained with abraded surfaces, where the grooves were roughly cylindrical in shape. It has been concluded that the technique can give a general quantitative index of roughness as defined by γ/μ 2 for any type of surface. If the interpretation of the results is carried further it can give in many cases (where the asperities are roughly coplanar) the average geometry of the asperities.

Effect of Groove Shape on the Frictional Hold of a Sheave on Polyester Rope

1985 ◽  
Vol 107 (1) ◽  
pp. 103-106 ◽  
Author(s):  
C. S. Albro ◽  
F. Liu
Keyword(s):  
Coefficient Of Friction ◽  
Relative Velocity ◽  
Line Tension ◽  
Maximum Tension ◽  
Groove Shape ◽  
Surface Data ◽  
The Coefficient Of Friction ◽  
Dry Conditions ◽  
The Difference ◽  
Lift Line

This paper discusses the effects of sheave groove shape, sheave diameter, and line tension on the frictional hold of polyester rope. A series of tests were conducted using five different sheaves, 5 and 9.2-cm-dia 2-in-1 polyester rope, under both wet and dry conditions. The frictional hold was determined from the difference in rope tension on opposite sides of a rotating sheave. The maximum tension on the high side was 245 kN. It was found that the coefficient of friction between polyester rope and smooth steel sheaves decreases with increase in rope tension for a given rope size. The 70-deg-V groove sheave shape demonstrated approximately 25 percent more frictional hold than the U-groove sheave shape. Holding capacity increases with sheave diameter. Large relative velocity exists between elastic lift line and sheave surface. Data will be used in a traction winch design.

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