For successful farming, soil cultivation is an essential first step. That is,the groundmust first be properly prepared before seeds or plants can be planted. Tillingmachines are used tobreak up the soil and are available for both small and large agriculturalusers. For those with smallhome gardens (e.g., less than about 200 square yards), a rototiller istypically sufficient. Mostrototillers include a motor driven shaft which carries any number of bladesand tines. As the shaftrotates, the blades rotate such that the tines serially enter and leave theground, thereby tearing upthe soil. While generally sufficient for small locations, rototillers are notpractical for large farmingapplications, where planting fields may cover thousands of square yards ofland. Large scale farmoperations typically use tractor-drawn tilling machines. These tillingmachines are generallyunpowered and consist of one or more rows of rotating discs. As the machine istowed, the rotatingblades dig into and turn over the soil. Additional tools may be coupled to thetilling machine, suchas a roller which typically follows the last row of discs and levels theprepared soil. Additionalblades may also be used to create furrows to prepare the ground for seedplanting.[0004] While current tilling machines generally perform their intendedpurpose, thesemachines suffer from a number of drawbacks. By way of example, rotating disctilling machinesmay have difficulty when turning rocky soil. For instance, when encountering alarge rock, theimpacted disc may be caused to pivot on its frame, resulting in inoperabilityof that disc for the
