An Onboard Load Measuring Device for Off-Highway Log Trucks
Authors
Mithun K. Shetty
Forest Engineering and Research Institute of Canada (FERIC), Vancouver BC V6T 1Z4 Canada
C. Kevin Lyons
Forest Resources Management, University of British Columbia, Forest Sciences Center, Vancouver BC V6T 1Z4 Canada
Abstract
This paper was motivated by the current concern of brake failure in off-highway log trucks descending steep grades and the lack of onboard weighing systems for off-highway log trucks. This paper considers using the leaf spring U-bolts as load transducers and is divided into two stages: preliminary strain measurement with a partially loaded off-highway tractor and finite element modelling (FEM) of a U-bolt from the tractor’s leaf spring suspension. Preliminary results showed that incremental strain at two locations on the U-bolt varied linearly with payload, for an incremental load of 22.5 kN. FEM of the U-bolt was carried out to predict the maximum incremental strain occurring on the U-bolt surface for an incremental load of 105 kN. Incremental strain on the top of the curved portion of the U-bolt was found to be relatively constant and close to the maximum level of incremental strain and is recommended as a preferred position for the strain gauges.
