A Method for Representing the Configuration and Analyzing the Motion of Complex Cable-Pulley Systems

Abstract

In this paper a systematic way of representing complex cable-pulley mechanism configurations and a method to analyze their motion is presented. This technique can also be used as an aid for synthesis. The cable-pulley system model that is being considered is planar and composed of three basic elements which are pulleys, blocks, and cables. A configuration table is used to identify the constraint equations by systematically defining the connections between the cables, pulleys, and blocks. The basic strategy is to use the constraint equations to generate the relationship between each variable and a subset of the variables identified as the inputs. A row reduction process on the system of constraint equations identifies the number of inputs and ultimately generates the relationships of each variable to the input(s). Results with different input variables can be easily obtained by a simple column interchange process. Examples are given to illustrate the procedure.