The effect of a slack-pulling device in reducing operator physiological workload during log winching operations

Abstract

The authors conducted a comparative test to determine whether the introduction of a hydraulic slack puller allowed reducing the physiological workload of operators assigned to log winching tasks. The tests were conducted in northern Italy, on the mountains near Como. The study involved five volunteer subjects, considered representatives of the regional logging workforce. Physiological workload was determined by measuring the operators’ heart rate upon completion of specific tasks. The slack puller improved the efficiency of downhill winching, since it allowed a single operator to pull out the cable on his own, without requiring the assistance of a colleague. However, introduction of the slack puller did not result in any reductions of operator physiological workload. The main stressor when working on a steep slope is moving up and down the slope: pulling a cable is only a secondary stressor. Any measures targeting secondary stressors are unlikely to produce dramatic reductions of operator workload.

Abstract

Practitioner Summary: Five operators were tasked with operating the same winch, with and without a slack puller. Heart-rate measurements showed that introduction of the slack puller did not result in any significant reductions of operator physiological workload, because the main stressor when working on a steep slope is moving up the slope.

Keywords::

• agriculture ergonomics
• equipment design
• operator physiological workload
• industrial ergonomics

Acknowledgements

Special thanks are due to Dr S. Poli and Dr A. Rapella for their assistance with the organisation of the field trials. The Authors are also grateful to Maxwald Gmbh for making their new winch available for the test.

Notes

^1. Email: [email protected]

^2. Email: [email protected]

Additional information

Funding

This study was funded by the Provincia di Como, within the scope of the EU Interreg Project PIT SAPALP.