Comparison of measured and simulated drawbar pull forsix wheeled vehicle with radial pneumatic tyres on sand

• To enable improved cross country characteristics of wheeled vehicles with individually controlled transmission on soft ground,suitable tyre/terrain models are needed. Here tyre/terrain models for simulating driving with both rigid and pneumatic wheels onsoft ground have been developed. A method to measure terrain parameters and drawbar pull for a six-wheeled vehicle on sand isproposed, tested and evaluated. The method is developed in order to be able to validate the proposed tyre/terrain models includingboth rigid and pneumatic wheels that are developed to simulate the behaviour of a six-wheeled vehicle with electric transmissionon soft ground. Tests were performed at different tyre pressures, and it is shown that the drawbar pull is vastly improved atlower tyre pressures. Since the tyre/terrain model uses terrain parameters such as pressure–sinkage and shear stress–displacementrelationships, the sand properties are measured with a Bevameter. Parameters in the pressure–sinkage relationship are estimated tofit the measured data. Both external and internal shearing properties of the sand are measured using a rubber coated shear ring anda shear ring with grousers, respectively. Shear curves of simple exponential form from the developed tyre/terrain models are shownto agree reasonably well with the measured shear behaviour. This will be the base in the development of a strategy to get improvedcross country characteristics of six-wheeled vehicles.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Farkostteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Vehicle Engineering (hsv//eng)

Nyckelord

mobility

wheeled vehicles

soft ground

Bevameter

Vehicle engineering

Farkostteknik

Publikations- och innehållstyp

vet (ämneskategori)

art (ämneskategori)