An indoor traction measurement system to facilitate research on agricultural tires

A soil bin-single wheel tester has been designed to study on soil-tire interaction. The soil bin features a 23-m long by 2-m wide by 1-m deep bin and an electric drive system is used to pull a carriage by two chains. The carriage has a capacity of testing three prototypes of tools in each run. Then a single wheel testing device was projected, built, instrumented and evaluated. The test tire on the moving carriage under the towing test mode was made to rotate and engage onto the soil surface in the soil channel through a chain drive system. Under the driving test mode, the test tire on the moving carriage was powered to rotate by a motor and an inverter with an additional pull provided by a chain mechanism connected to an electromotor. Respective transducers were positioned at various localities interfaced to a data acquisition system to measure and save tire horizontal and vertical forces, tire sinkage, tire speed and carriage speed. The performance of the testing facility was evaluated and validated during some initial tests. Static calibration tests on various associated transducers showed excellent linearity with coefficients of determination (r 2 ) of close to 1. The comparison between observed and predicted values of motion resistance ratio using Wismer and Luth model showed an accuracy of ±20 per cent.