AbstractThe current paper presents an approach to system design of combined electro-hydraulic-mechanical systems. The approach is based on the concurrent handling of the topology as well as the design parameters of the mechanical, hydraulic and controller sub systems, respectively. Based on an initial design the procedure attempts to find the optimal topology and the related parameters. The topology considerations comprise the type of hydraulic pump, the employment of knee linkages or not as well as the type of hydraulic actuators. The design variables also include the signals to the proportional valve in a number of predefined load cases as well as the hydraulic and mechanical parameters. Design criteria such as system cost, efficiency, weight and structural stability are considered.