Design and fabrication of an ergonomic handlebar structure of a hand tractor for vibration suppression

Issue Date

3-2016

Abstract

The hand tractor is one of the major farm machineries used by Filipino farmers. It exposes farmers to excessive hand-arm vibration (21.09 m s-2 at 2400 rpm), which may lead to disabling diseases if not controlled or reduced. This study evaluated the effectiveness of changing the design of the handlebar structure of the locally made hand tractor to reduce vibration transmitted to operators during idling operation of the tractor. The actual vibration during idling operation of the hand tractor was measured based on the standards set by ISO 5349:2001. Using the results of the study by Bureerat and Kanyakam (2007) as basis for the improvement of the handlebar design, the principles set by the Philippine Agricultural Engineering Standards (PAES), and the engineering design process, an improved handlebar design was fabricated. The alterations made on the original handlebar design include: change in the material of the main frame from galvanized iron steel pipe to black iron steel pipe of greater diameter which significantly reduced the manufacturing cost and increased the strength of the structure through the principle of polar moment of inertia, addition of square steel bar stiffeners to the handlebar structure which increased the strength and rigidity of the structure, and inclusion of bending in the design which helped to dissipate the vibration. With the installation of the new design, the vibration transmitted to the operator was reduced by as much as 55.87% at 2400 rpm, 40.94% at 3000 rpm, and 19.87% at 3600 rpm. Moreover, the proposed design weighed less (by 25%) and was cheaper (by 5.11%, considering labor and production) than the original design.

Source or Periodical Title

Philippine Agricultural Scientist

ISSN

0031-7454

Volume

99

Issue

1

Page

58-67

Document Type

Article

Physical Description

illustrations, tables, graphs

Language

English

Subject

Daily vibration exposure, Hand tractor, Hand-arm vibration syndrome, Handlebar structure design, Vibration exposure duration

Digital Copy

yes

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