High ground clearance self-propelled sprayers usually work in complex road conditions. Due to the large body mass, wide spray boom breath and high center of gravity, the body and spray boom swing sharply during work, which affects operation quality and even endangers safety. This paper proposes a control plan for timely-started active hydro-pneumatic suspension, and designs a fuzzy PID control system based on genetic algorithm optimization. First, MATLAB software is used to simulate and analyze the model, so that the fuzzy PID control optimized by genetic algorithm is obtained. When the sprayer drives on D-grade road, as the speed increases, in comparison between the damping effect of the active suspension and traditional passive suspension, the corresponding root mean square value of vehicle body vibration acceleration decreases by 11.36 and 12.36%, respectively. On the E-grade road surface, with the increase of speed, the corresponding root mean square value of vehicle body vibration acceleration decreases by 13.25 and 14.89%, respectively. Based on indoor bench experiments, the proposed control strategy was verified. Under field road excitation, when the sprayer traveled at 5 km/h, the root mean square acceleration values of the passive and active suspensions were 1.080 and 0.847 m/s2, respectively; when the sprayer traveled at 8 km/h, the root mean square acceleration values of the passive and active suspensions were 1.412 and 1.125 m/s2, respectively, with the root mean square values of vibration acceleration reduced by 21.57 and 20.33%, respectively. Under sand-gravel road condition, when the sprayer traveled at 5 km/h, the root mean square acceleration values of the passive and active suspensions were 1.149 and 0.891 m/s2, respectively; when the sprayer traveled at 8 km/h, the root-mean-square acceleration values of the passive and active suspensions were 1.572 and 1.229 m/s2, respectively, with the root mean square values of vibration acceleration reduced by 22.45 and 21.82%, respectively. During the active control process, the suspension displacement is always kept within the limited range, and as the vehicle speed and road surface level increase, the active suspension has a significantly better damping effect than the passive suspension, which proves effectiveness of the active damping scheme.

The application possibility of impregnating compounds for maintenance of rubber components of a pneumatic suspension of road machines under different temperature conditions has been assessed. Solid oil (the cheapest general-purpose plastic grease) and anaerobic material of AN-1U grade (richer impregnating compound) were used as impregnating compounds. It was found out that the use of impregnating compounds for maintenance of rubber components of a pneumatic suspension of road machines made possible to increase their resistance to the effect of negative temperatures, to minimize material cracking and as a result to increase service life of the suspension.

The operation conditions of nonmetallic elements of the pneumatic suspension of road-making machines have been studied and analyzed. Evaluation of the strength characteristics of the nonmetallic elements of the pneumatic suspension under the influence of negative temperatures was carried out. It was found out by experiments that the influence of negative temperatures resulted in an increase in stiffness of a rubber part of an air cell. It was determined that for increasing resistance of the nonmetallic elements of the pneumatic suspension to the influence of negative temperatures it was necessary to use anaerobic impregnating compounds.

This study develops a new type of semi-active dual-chamber hydro-pneumatic inerter-based suspension (SADHPIS) based on the ‘inerter–spring–damping’ vibration isolation system and semi-active control. The mathematical model of SADHPIS is linearised to match the nonlinear SADHPIS system with a linear control strategy, and the equivalent parameters are calculated. A linear–quadratic–Gaussian (LQG) controller that matches the nonlinear characteristics of the SADHPIS system is designed. Furthermore, the performance of a quarter-vehicle model with SADHPIS is analysed and compared with that with normal semi-active hydro-pneumatic suspension (SAHPS). Simulation results show that the performance of SADHPIS is better than that of SAHPS, indicating that ride comfort and handle stability are improved greatly in SADHPIS. A prototype is also developed, and a comparative bench test is conducted to verify the accuracy of the simulations. SADHPIS can realise adjustable inertia with a small space and low energy consumption. This work provides new insights for research on variable inertia, promotes the matching of inerters and hydro-pneumatic suspension systems and further proves the practical application value of hydro-pneumatic inerter-based suspension.

The purpose of this paper is to analyze the performance of the hydro-pneumatic suspension system (HPSs) of a mining dump truck on ride comfort under operating conditions. To achieve goals, a 3-D full-vehicle vibration model of a mining dump truck with 10 degrees of freedom is set up to analyze the effects. A nonlinear mathematical model is set up based on the nonlinear characteristics of the HPSs to determine their vertical force which is connected with a 3-D full-vehicle vibration model. The effects of operating conditions on a heavy truck ride comfort are respectively analyzed through the values of the root mean square of acceleration responses of the vertical cab, pitch and roll angles of cab (awc, awphi and awteta). The analysis results indicate that the survey conditions have a great influence on vehicle ride comfort. Especially, the values of awc, awphi and awteta with the poor road surface condition respectively reduce by 43.1%, 45.9% and 61.8% compared to the very poor road surface condition at vehicle speed of 30 km/h and full load.