Digital hydraulics in workboat propulsion control

Abstract

This paper introduces application of digital hydraulics in workboat propulsion control. The performance requirements of the propulsion control application can be considered to be moderate for hydraulics but because the application is safety critical robustness and reliability of the hydraulics are highly appreciated in harsh operating environments. Low cost and compact size are also preferred. Control method introduced in the paper is meter-out control of a hydraulic cylinder drive using a digital flow control unit. Performance of the digital propulsion control hydraulics is tested in test bench and a simple lifetime analysis is made and compared to requirements of standards concerning the application. Reliability and fault tolerance are also discussed.