Configurations of tracked vehicle for development of subsea mining machines with improved mobility on soft soil

Abstract

The National Institute of Ocean Technology (NIOT) has been actively involved in developing technology for a deep-sea mining machine designed to extract polymetallic nodules from depths ranging between 5000 and 6000 metres in the Indian Ocean. Designed specifically to collect nodules from soft seabeds, the project focuses on the development of a crawler-based mining machine. Manoeuvring and maintaining stability in low-cohesion soil with a bearing capacity below 10 kPa presents significant challenges. This paper conducts a study to determine the suitable track configuration, crucial for improving vehicle traction under deep-seabed soil conditions. The research compares explicitly the traction efficacy of long dual-track and short four-track configurations with the same contact area and bearing pressure on soft soil. Additionally, soil-grouser interaction studies were conducted using numerical simulation techniques to assess the mining vehicle's permissible sinkage and improve its traction performance. This involved developing a soil-machine interaction environment and simulating the dual and four-track configurations with seabed soil parameters. The research further compare the efficacy of two-tracks long-length and four-tracks short-length configurations with the same contact area and bearing pressure on soft soil. The drawbar pull simulations of the vehicle were conducted using dynamic and mathematical simulation tools in MATLAB to evaluate the mobility characteristics of tracked vehicle configurations under varying operational conditions. Based on the numerical results, the prototype model will be developed, and its performance under various traction conditions will be evaluated.