Ergonomic evaluation of forestry crane partial automation system

Abstract

Harvesters and forwarders are the main part of cut-to-length logging system equipment. Perfection of the hydraulic cranes have a very large impact on the overall operating efficiency of these forest machines. An analysis of impact of the John Deere crane partial automation option «Intelligent Boom Control» (IBC) on the work cycle and workload of forest machines operators is described in this article. Two machines equipped with IBC systems were studied in field conditions. Differences in frequency and duration of telescopic extension boom control activations were identified. It was determined that as a result of automation, one of the degrees of freedom of the crane controls is practically completely excluded from use in the case of forwarder (decrease by about 10 times). A significant reduction in the duration of its use is observed in the case of harvester (decrease by about 2 times). As a result, this saves the psycho-physiological resources of the operator for more efficient use of remaining degrees of freedom, which, coupled with a simpler and more intuitive logic of the controls operation, improves the productivity, accuracy and safety of cut-to-length logging. In addition, a simpler work algorithm reduces the level of stereotyping of the operator’s actions, fatigue and loss of attention, which usually come out at the end of the shift.