Evaluation of Lightweight Grousers for Agricultural Tracks: New Solution for Soft Soil Problem

Crop maintenance machinery for herbicide spraying and spreading fertilizer input has been the current practice for paddy production in Malaysia, especially in large granary areas. Soft soil issues in paddy fields have become a significant problem and prevent heavy machinery from conducting field operations. Current paddy prime movers use rubber wheels that produce high ground contact pressure onto the soil for crop maintenance operation. With high ground contact pressure, the probability of machines sinking into the soil, or bogged down, is higher and can cause the machine to get stuck. This also can result in hardpan damage (Mandang et al., 2000). Recently, prime agriculture mover uses steel track that has the issue on-road or soil damaged due to the grousers material use. Engineering Research Centre in Malaysian Agricultural Research and Development Institute (MARDI) have found an alternative solution for this issue by developing and replacing all the wheels on a standard 12.75 kW (17 hp) High Clearance Prime Mover with Polyoxymethylene (POM) grousers equipped on triangular track-based system. This paper aims to find the optimal size of grousers for POM material to be installed on the high clearance machinery for alternative solutions to solve problematic soil and its effect on the soil. Polyoxymethylene or POM was chosen due to its excellent rigidity, impact toughness, abrasion resistance, creep resistance and solvent resistance, hydrolytic stability fatigue endurance, low coefficient of friction lightweight. To develop suitable POM grousers, a triangular track-based system has been tested with three different length sizes of rectangular wooden track grousers 13 x 4 x 4 cm, 15 x 4 x 4 cm, and 18 x 4 x 4 cm that could be quickly mounted on or removed from D4 track chain, permitting rapid sequential testing on the soft soil area. Field tests have been conducted at MARDI Seberang Perai, Pulau Pinang. The measured parameters were slippage, machine sinkage, and soil compaction.  The high clearance prime mover obtained slippage of 16.4% using 13cm shoes and 18.2% for 15 cm 22.2% for 18 cm accordingly, and sinkage for all shoe size were less than 30 cm.