A proportional electrohydraulic control valve is an ideal interface between the electronic “brains” of today’s powerful microprocessors and other super chips and the muscle of the hydraulic system. In many machines, hardware constraints result in controls which are difficult for a human operator to manage and require considerable experience and skill to become proficient. The microprocessor can be used to convert the familiar X-, Y- and Z axis thinking of an operator into the complex motions of the basic machine and thus produce a machine which is at the same time easy to use and predictable with minimal experience.
The purpose of this paper is to relate the authors’ experiences in building a three axis machine actuated by a computer controlled, proportional electrohydraulic valve. It deals with the basic machine, the hydraulic system, the electronic system and the software.