AbstractMany multi-axle applications use electro-hydraulic control systems with proportional valves. The proportional steeringsystem can satisfy common engineering requirements, but it is likely to fail if the steering angle or load changes drasticallybecause of poor dynamic characteristics, including dead zones, hysteresis, and frequency response. An electro-hydraulicservo steering system with servo solenoid valve is proposed to guarantee a precise dynamic response and good price–performance ratio of the closed-loop system. A co-simulation model based on ADAMS and AMESim was established toanalyze the influence of the main parameters on steering performance. The mechanical model includes tire and groundparts, and the steering load can be simulated accurately. The simulation results show that dead zones, hysteresis, and frequency response of control valve have great influence on the steering performance, and the servo solenoid valve isproper for this system. The servo steering system was applied to the actual seven-axle all-terrain crane, and the systemperformance was extensively tested. The experiment results show that the system has good accuracy and trackingresponse performance in several real situations, including parking and high-speed transport