Modelling and study of active vibration control for off-road vehicle

Abstract

In view of special working characteristics and structure, engineering machineries do not have conventional suspension system typically. Consequently, operators have to endure severe vibrations which are detrimental both to their health and to the productivity of the loader. Based on displacement control, a kind of active damping method is developed for a skid-steer loader. In this paper, the whole hydraulic system for active damping method is modelled which include swash plate dynamics model, proportional valve model, piston accumulator model, pilot-operated check valve model, relief valve model, pump loss model, and cylinder model. A new road excitation model is developed for the skid-steer loader specially. The response of chassis vibration acceleration to road excitation is verified through simulation. The simulation result of passive accumulator damping is compared with measurements and the comparison shows that they are close. Based on this, parallel PID controller and track PID controller with acceleration feedback are brought into the simulation model, and the simulation results are compared with passive accumulator damping. It shows that the active damping methods with PID controllers are better in reducing chassis vibration acceleration and pitch movement. In the end, the test work for active damping method is proposed for the future work.

An active oscillation reduction method for off-highway front loaders

“…The same work suggests the adoption of the closed-loop displacement control (DC) architecture, for its known advantages in reducing energy consumption of mobile off-road vehicles, as further discussed in many other studies (significant examples are) 6,7 but also for its effectiveness on oscillation reduction. Such claim is supported by past research: Zhang and Chen 8 show a simulation study on proportional-integral-derivative (PID) controller with acceleration feedback designed for a skid-steer loader. The results show a reduction of vertical cabin acceleration up to 46% with respect to the system without ride control.…”

Robust Pitching Disturbance Force Attenuation for Tractor Considering Functional Constraints

“…Velmurugan et al [56] presented the experimental values of force disturbance in tractors. Zhang and Chen [17] developed a formulation to determine the vibration experienced by the tractor due to road inputs. Jaiswal et al [57] developed a terrain model for a tractor with front loader.…”

“…It was found that variation in ω has a higher effect on the performance. In the literature, the attenuation level reported is of the order of 40 % [10], [17], [18], [20]. Based on this, a lower bound for attenuation was considered to be 50 %.…”

Dynamic characteristics of coupling model of valve-controlled cylinder parallel accumulator

“…Additionally, Yang and coworkers [5] show that the accumulator can suppress the water hammer phenomena of hydraulic steering systems and prove that the suppression effect on the water hammer is optimized when the inherent frequency of the water accumulator is equal to or close to the frequency of the water hammer. In references [6][7][8][9][10][11][12], hydraulic potential energy regenerative vehicles are designed to reduce the vibration amplitude of vehicles on rough roads and decrease the structural noise. The motor location, the hole area of the valve, the inner diameter of pipelines, and the accumulator pressure are key factors contributing to suspension performance.…”