An evaluation of arborist handsaws

Date
2009-01-01
Authors
Mirka, Gary
Jin, Sangeun
Mirka, Gary
Hoyle, Jeff
Journal Title
Journal ISSN
Volume Title
Publisher
Source URI
Altmetrics
Authors
Mirka, Gary
Person
Research Projects
Organizational Units
Journal Issue
Series
Abstract

A review of the scientific literature reveals little research on the ergonomics of handsaws and no literature on the specific challenges of arborist saws (saws for cutting and pruning living trees). This study was designed to provide some insight into the effects of saw design and height of sawing activity on the biomechanical response of the upper extremity. Eighteen participants performed a simple sawing task at three different heights using six different arborist handsaws. As they performed this task, the electromyographic activity of several muscle groups of the forearm (flexor and extensor digitorum), arm (biceps brachii long and short heads) and shoulder girdle (posterior deltoid, infraspinatus and latissimus dorsi) were sampled. Also gathered were the wrist postures in the radial/ulnar plane at the beginning and ending of the sawing stroke, the time to complete the sawing task and a subjective ranking of the six different saws. The results show an interesting mix of biomechanical and subjective responses that provide insight into handsaw design. First, there were tradeoffs among muscle groups as a function of work height. As work height increased the biceps muscles increased their activation levels (∼19%) while the posterior deltoid activity decreased (∼17%) with the higher location. The results also showed the benefits of a bent handle design (average 21% reduction in ulnar deviation). The subjective responses of the participants generally supported the productivity data, with the saws demonstrating the shortest task completion time also being the ones most highly ranked.

Description
<p>This is a manuscript of an article published as Mirka, Gary A., Sangeun Jin, and Jeff Hoyle. "An evaluation of arborist handsaws." <em>Applied ergonomics</em> 40, no. 1 (2009): 8-14. doi: <a href="https://doi.org/10.1016/j.apergo.2008.02.011" target="_blank" title="Persistent link using digital object identifier">10.1016/j.apergo.2008.02.011</a>. Posted with permission.</p>
Keywords
handsaw, shoulder, wrist, biomechanics
Citation
Collections