Publication

Abstract : In controlling the orientation of an object, it is always desired to have a more intuitive form of controller or an input device as it helps the user adapt to it at a faster pace, hence making it more productive. This paper focuses on the development of a prototype and application of an intuitive serial chain mechanism to measure orientation. This user driven mechanism, referred to as 3-Revolute Orientation Sensing Mechanism (3-ROSM), proposed elsewhere by the authors, is a serial chain mechanism with three intersecting axes and has rotary encoders to measure the joint angles. It is also gravity balanced to prevent reorientation of its links due to the action of gravity. This reduces the effort needed by the user to move its links and also its dependence on load bearing servo motors. It also emulates the joint system in a human wrist and reduces the overall load acting on the user’s hand while gripping the end-effector. The gravity compensation is achieved through the placement of counterweights along and orthogonal to the joint axis under consideration. This makes the 3-ROSM more adaptable to desirable or undesirable load variations. The additional features of this device are its simplicity, low cost, energy efficiency and wide available workspace with which the user can operate this device. To demonstrate its usability and versatility, an easy to assemble physical prototype of the 3-ROSM was designed and developed, which has encoders mounted on its joint axes and was used in two different applications. First, in controlling a 3-axis motorized camera mount and second, navigating the position and orientation of the view-camera in a CAD software. © Springer Nature Switzerland AG 2019.