Increasing the Comfort of the Harianavi Bullocks by Reduction of Contact Pressure on Neck by Designing a Body Contoured Yoke.

A yoke is an interface between bullock power and actual work to be performed. The yoke is worn on the neck of the bullocks and is secured by a belt around the neck. The bullocks push the yoke with their shoulders, hump and neck; therefore, the work is performed. Neck of the bullock is subjected to a high pressure which damages the body tissues. Consequently, bullocks are subjected to injuries, pain and fatigue that limit their performance. The neck seats are shaped similar to the neck profile of the bullocks which ensures high contact area between animal body and neck seat leading to lesser pressure and more animal comfort. The neck of a bullock was digitized using an optical scanner and a large number of points were obtained. The 3-D model was created on the digitized points, and the neck seat was developed subsequently. The contact analysis was performed using the augmented Lagrangian formulation option of Ansys Workbench for predicting contact pressure. The results of the body contoured yoke are compared with that of a flat wooden plank yoke and a cylindrical yoke. A substantial reduction of contact pressure and indentation on the neck has been found for the body contoured yoke. Conversely, the contact pressure was found much higher for other two types of yokes.

Case Study: Composite Material Yoke Versus Wooden Yoke for Bullocks' Comfort.

This article addresses the designing of a yoke used to get work output (plowing) from bullocks. The yoke profile was designed in compliance with the profile of the bullock's body for maximum contact area. Unlike the crude, wooden yoke used in rural India, where modern tilling equipment like a tractor is not affordable, the present yoke was smooth, free from sharp edges, and light in weight. A field study was carried out with bullocks using composite and wooden yokes. The fatigue of bullocks was measured in terms of respiration rate and heart rate. Data revealed that bullocks had less fatigue with composite material yoke than with the wooden yoke. The experimental investigation also showed that at a 30º angle of pull, bullocks feel maximum comfort when they are used for plowing purposes.