Transversal vibrations of a toothed belt in linear drives during operation

Abstract In this paper a mathematical model for the study of the interaction of longitudinal and transversal vibrations in a stretched string is presented. The study implies an existence theory for time periodic transversal vibrations generated by a horizontal excitation of one of the end-points of the string. The conditions for the existence of this parametrically excited time periodic vibrations are evaluated in a practical application. The innovative character of the results obtained concern the application of an operator method to a system of nonlinearly coupled wave equations modeling the dynamical behaviour of a strectched string where unite elasticity is taken into account. It may be known that in the literature little attention has been paid to a rigorous analysis of time periodic solutions for systems of partial differential equations.

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Design and Analysis of a Wearable Upper Limb Rehabilitation Robot with Characteristics of Tension Mechanism

Applied Sciences ◽

10.3390/app10062101 ◽

2020 ◽

Vol 10 (6) ◽

pp. 2101 ◽

Cited By ~ 1

Author(s):

Zaixiang Pang ◽

Tongyu Wang ◽

Zhanli Wang ◽

Junzhi Yu ◽

Zhongbo Sun ◽

...

Keyword(s):

Upper Limb ◽

Human Body ◽

Wrist Joint ◽

Traction Force ◽

Rehabilitation Robot ◽

Upper Limb Rehabilitation ◽

Freedom Of Movement ◽

Human Arm ◽

Toothed Belt ◽

Limb Rehabilitation

Nowadays, patients with mild and moderate upper limb paralysis caused by cerebral apoplexy are uncomfortable with autonomous rehabilitation. In this paper, according to the “rope + toothed belt” generalized rope drive design scheme, we design a utility model for a wearable upper limb rehabilitation robot with a tension mechanism. Owing to study of the human upper extremity anatomy, movement mechanisms, and the ranges of motion, it can determine the range of motion angles of the human arm joints, and design the shoulder joint, elbow joint, and wrist joint separately under the principle of ensuring the minimum driving torque. Then, the kinematics, workspace and dynamics analysis of each structure are performed. Finally, the control system of the rehabilitation robot is designed. The experimental results show that the structure is convenient to wear on the human body, and the robot’s freedom of movement matches well with the freedom of movement of the human body. It can effectively support and traction the front and rear arms of the affected limb, and accurately transmit the applied traction force to the upper limb of the joints. The rationality of the wearable upper limb rehabilitation robot design is verified, which can help patients achieve rehabilitation training and provide an effective rehabilitation equipment for patients with hemiplegia caused by stroke.

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New Toothed Belt Matches Various Pulley-Profiles

Volume 6: 8th International Power Transmission and Gearing Conference ◽

10.1115/detc2000/ptg-14410 ◽

2000 ◽

Author(s):

Frank H. Schaefer

Keyword(s):

Sound Intensity ◽

Belt Drive ◽

Special Test ◽

Intensity Measurements ◽

Test Conditions ◽

Toothed Belt ◽

Quality Of Motion ◽

Center Distance ◽

Dynamometer Test

Abstract This paper examines the possibility of a new toothed belt construction to run in various pulley-types. The measurements from a laboratory dynamometer test stand show the belt life under special test conditions by use of HTD-, STPD- and RPP-pulleys, each with an angle of wrap of 180°. In case of locked center distance the increase of torque causes tooth climbing until belt jumping occurs. The pretension was brought into line with the torque each time the torque was increased and the jumping limit torque was determined. From literature it is expected that the results for the behavior of the HTD- and the RPP-pulley are similar. Another parameter to describe the quality of motion is the noise. Here sound power is a very effective descriptor of how noisy an object is. It was determined from sound intensity measurements for HTD- and STPD-pulleys. The ratio of the toothed belt drive used for the noise measurement was 0.63.

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Kinematic Nonuniformity of the Rotation of a Toothed Belt Transmission with a Composite Pulley

Russian Engineering Research ◽

10.3103/s1068798x20090130 ◽

2020 ◽

Vol 40 (9) ◽

pp. 705-709

Author(s):

Zh. Mukhamedov ◽

V. M. Turdaliev ◽

A. A. Kosimov

Keyword(s):

Toothed Belt ◽

Belt Transmission

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Modelling of Power Transmission Systems for Design Optimization and Diagnostics of Gear in Operational Conditions

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.210.108 ◽

2013 ◽

Vol 210 ◽

pp. 108-114

Author(s):

Grzegorz Peruń ◽

Bogusław Łazarz

Keyword(s):

Dynamic Model ◽

Power Transmission ◽

Test Stand ◽

Laser Vibrometer ◽

Operational Parameters ◽

Operational Conditions ◽

Power Transmission Systems ◽

Laboratory Examinations ◽

Transversal Vibrations ◽

Dynamic Phenomena

This article presents the author's dynamic model of power circulating gear test stand. It was assumed, that properly defined and next identified model can be used to analyze dynamic phenomena in meshing and bearings of gears and allows optimizing their construction, especially to minimize their vibroactivity. The article includes description of the construction of a test-stand, as well as short characteristic of the dynamic model. Afterwards it was presented verification, whether the model was correctly fine tuned. For verification purpose, were conducted laboratory measurements of velocity of transversal vibrations at the test-stand using laser vibrometer. Results of laboratory examinations were compared with the results achieved during computer simulation. Developed and presented dynamic model take into account a number of design, technological and operational parameters of gear. It was also presented algorithm of researches aimed at minimizing the vibroactivity of gear.

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