Highlights Chassis suspension grease lubrication state significantly alters vehicle dynamics, operator comfort, and boom stability in a self-propelled sprayer. Dry chassis suspension configurations increased chassis and boom stability, but reduced operator comfortability due to higher system rigidity. Proper greasing improved operator ride quality, but led to greater chassis motion and boom height variability at higher speeds. ABSTRACT. Due to the tall nature of self-propelled sprayers and their high center of gravity, operators can experience intense amounts of movement when these machines come to an abrupt stop or turn sharply at high speeds. For this reason, it is important to understand the chassis suspension and how different design factors affect machine dynamics. This research focused on the chassis suspension strut assembly of a 408R John Deere Self-Propelled Sprayer; this assembly contains grease locations that operators are recommended to grease at regular intervals of operation. To determine the machine performance differences due to grease variability, testing was conducted on a test stand and in the field with two primary suspension configurations: (1) a “dry” configuration with the suspension spindles wiped clean of all grease from the joint, and (2) a “fully greased” configuration. A comprehensive data acquisition package was strategically installed on the machine before conducting testing to derive an A to B comparison of chassis suspension dynamics, operator comfort, and motion stability of both the chassis and boom. The results proved that the state of grease on the suspension spindles dramatically affected the machine’s dynamic performance. The results revealed that when the machine was appropriately greased, the operator was more comfortable, but at the cost of producing a less stable chassis and boom system. In contrast, insufficient grease increased chassis and boom stability, but the rigidity resulted in the operator experiencing more discomfort due to absorbing high amounts of accelerations. Overall, the testing provided insightful machine performance differences to better understand the performance variability caused by a customer’s grease maintenance level. Keywords: Chassis suspension, Grease, Lubrication, Maintenance, Performance, Sprayer, Vehicle dynamics.
Kueker et al. (Thu,) studied this question.