Torque Requirements and Forces Generated by a Deep Tilling Down-Cut Rotary Tiller

Abstract

The paper reports the measurement and analysis of torque requirements and force/thrust generated by an experimental deep tilling (up to 500 mm) down-cut rotary tiller. To quantify these two parameters, soil dynamic parameters including soil shear strength and soil- metal friction were determined. The torque, thrust generated, depth of tillage, rotational and forward travel speed were measured at the rate of 2.4kHz under field conditions using a tractor mounted on-board computer and a commercial data acquisition system. The ratio of the forward speed to the travel speed was determined from the measured forward travel and rotational speeds. Depth of tillage was determined using a ten-turn potentiometer displacement transducer. Generated force and torque requirements during down-cut tillage test-runs were measured using suitably placed strain gauge force transducers and a load cell on a specially designed tool-frame carrier. Sufficient data on soil dynamic parameters pertinent to tillage were collected using a torsional soil shear device mounted on a separate tool-frame and tractor for each tilling depth. Soil water content was determined for each series of tests using the standard oven procedure. Torque requirement and the associated forces generated were determined and analyzed for each depth of tillage, dynamic soil parameters and bite length.