Experimental Study on the Physical and Frictional Properties of Cassava Stems

Abstract

Cassava (Manihot esculenta) stems are essential planting materials, and their physical and frictional properties are important for the practical design of planting, conveying and handling equipment. This study experimentally evaluated four cassava varieties, TMS 4(2) 1425, TME 419, TMS 30572 and TMS 30555, obtained from the Teaching and Research Farm of Rufus Giwa Polytechnic, Owo, Nigeria. Freshly harvested 12-month-old stems were cut into 250 mm stakes for frictional tests, while stem dimensions were assessed using 300 mm samples. Measurements were taken on days 1, 3 and 5 after harvest under dry-season conditions. A locally fabricated measuring device was used to determine the angle of friction, coefficient of friction, bulk friction coefficient and coefficient of rolling resistance on wood, stainless steel and mild steel surfaces using fabric and plastic ropes. Stem moisture content, diameter, number of nodes and density were also determined. Stem density decreased after harvest in all varieties, ranging from 328.07 to 391.29 kg/m3. TMS 4(2) 1425 recorded the highest density, mean number of nodes per 300 mm and mean stem diameter, whereas TME 419 had the lowest density. The coefficient of friction ranged from 0.348 to 0.579 for the fabric rope and from 0.344 to 0.581 for the plastic rope. Bulk friction coefficient ranged from 0.061 to 2.057, while rolling resistance ranged from 4.076 to 7.923. Frictional responses varied with variety, contact surface, rope material and moisture condition. The results provide experimentally derived parameters that can support the design and adjustment of cassava stem handling and planting equipment.