Studies on the sinkages of rigid plain wheels and lugged wheels on TRI-1 lunar soil simulant

Abstract

This paper summarises the experimental work and analytical work carried out to determine the wheel sinkage of plain rigid wheels and lugged wheels, traversing on TRI-1 Lunar Soil Simulant (Plain and lugged wheels: small wheel- 160 mm × 32 mm and large wheel- 210 mm × 50 mm) with different number of lugs (N = 8, 12, 16) and lug height (h = 5, 10, 15 mm). Bekker and Reece pressure sinkage models are considered to determine the theoretical sinkage, and outlined in the present study. Comparisons of the analytical results with the experimental results are also carried out. The comparisons hold good for plain rigid wheels and in 2 cases, for lugged wheels (Small and Large), with 16 lugs of height, 5 mm. For all other combinations of lugged wheels (no. of lugs = 8, 12 and height of lugs = 5 mm, 10 mm and 15 mm), the predicted values are found to be less than the experimental values. For efficient functioning of the rover, optimization of wheel dimensions is a must.A new sinkage model accounting gravity effect and aspect ratio is developed, based on experimental results for wheel sinkages on TRI-1 simulant, the range of results obtained for different cases are examined.