A Case Study on Quantifying the Workload of Working Machine Operators by Means of Psychophysiological Measurements

Abstract

In this study of eighteen wheel loader operators, test-driving a machine in three different traction force settings, we examine if a workload index derived from psychophysiological measurements of heart rate, finger temperature, skin conductance, respiration rate and end-tidal CO 2 -concentration in exhaled air can be easily used to assess operator workload in sufficient detail to use it as a complement to traditional subjective evaluations in machine testing, either of real machines or in a human-in-the-loop simulator. In a longer perspective, such measurements are expected to play a role in a workload-adaptive operator assistance system. However, the findings do not give support for this vision. Instead they indicate that other types of measurements than what have been used in our study should be employed if ease of use for practitioners such as test engineers is in focus, but also that other factors than just machine operability must be considered to have a great influence on the operator workload.

Towards Finding the Optimal Bucket Filling Strategy through Simulation

“…Having completed the simulation study the question arises if this is also how human operators fill a bucket in real work. The results from various physical testing of wheel loaders are available for such endeavor, for example [13] with 18 operators participating, which has been further analyzed in [14], and the subsequent study presented in [15] with 73 operators participating, further analyzed in [16]. The large number of test participants, operating in real work in three different bucket loading applications makes the latter study especially attractive.…”

Design and Study of Mechanical Cutting Mechanism for Submarine Cable Burial Machine

“…In order to ensure the quality of the operation and avoid excessive vibration, there must be certain limitations on the chain blade's movement speed. According to the experiments in [22], the former Soviet scholars recommended a chain blade linear velocity of 1 to 2 m/s. In this paper, the mechanical cutting components are selected with a chain blade movement speed of 1.5 m/s, resulting in a corresponding soil dispersion coefficient of 0.85.…”