Implementation of Specific Displacement Diagrams for the Control of Kinetic Sculptures with Yaskawa Electronic Cams

Abstract

Electronic cams are used for different manufacturing systems, but in terms of displacement diagrams, they have common characteristics. The emphasis is usually placed on maximum accuracy, the machine cycle time and the displacement diagram has a simple shape. This paper addresses a completely different case, which shows that the use of electronic cams is very diverse. A Yaskawa’s electronic cam was used to control the kinetic art sculptures. It was necessary to develop an implementation that will be able to accommodate a large number of very long and complex displacement diagrams. Sculptures contained up to 150 interpolating axes and their programs took up to half an hour. The proposal builds on the basic animation and designer’s demands, but it must comply with all limits of the mechanism (maximum speed, torque, etc.). The classic electronic cam uses a data table and interpolation function. This approach has been replaced with a new feature that composes the movement from polynomial of the 5th order. For this purpose, it was developed an independent software tool. The final displacement diagram is composed by defining the 0th, 1st, and 2nd derivatives at the key points. This method of design has proved to be very effective, and in addition, this implementation brought a significant saving of memory and reducing of computational complexity.