Integrated semi-active seat suspension for both longitudinal and vertical vibration isolation

Abstract

“Functional integration” is to integrate two or multiple systems or mechanisms that are independent with each other and to realize the two or multiple functions using only one actuation system. Maximization of engineering applications of actuation systems could be achieved through the use of the “functional integration” concept-based structural design. In this article, an integrated semi-active seat suspension, mainly composed of a switching mechanism, a transmission amplification mechanism, and a damping force- or torque-controllable rotary magnetorheological (MR) damper working in pure shear mode, for both longitudinal and vertical vibration attenuation, is proposed, designed, and fabricated. The switching mechanism employs the parallelogram frames as a motion guide which keeps the seat moving longitudinally and vertically. Both longitudinal and vertical motions are transformed into a reciprocating rotary motion that is transmitted to the rotary MR damper after an amplification by a gear mechanism. The torque generated by the MR damper can be tuned by adapting the applied current in real time, and hence, effective two-dimensional vibration control of the seat could be realized. The mathematical model of the semi-active seat suspension system is established, and vibration isolation performance of the system is simulated and analyzed. Based on the established experimental test rig, the prototype of the semi-active seat suspension system is tested, and the results of the mathematical model and the experimental test are compared.

A Systematic Literature Review of Various Control Techniques for Active Seat Suspension Systems

“…Undoubtedly, the effects of the vibration, which comes from all the other directions are not as severe as those from the vertical direction. Plenty of researches have been conducted on the 1 DOF active seating suspension system in the vertical vibration, whereas other researches have been focused on multiple DOF seating suspension system in multiple axis directions, for example, in the vertical and horizontal vibrations [46] or vertical and longitudinal vibrations [47]. Different types of actuators with various mechanism structures are normally adopted in these multiple DOF seating suspension systems.…”

“…Sci. 2020, 10, x FOR PEER REVIEW 6 of 24 suspension system in multiple axis directions, for example, in the vertical and horizontal vibrations [46] or vertical and longitudinal vibrations [47]. Different types of actuators with various mechanism structures are normally adopted in these multiple DOF seating suspension systems.…”

A Review of Low-Frequency Active Vibration Control of Seat Suspension Systems

“…Semiactive vibration control of a seating system utilizes the characteristics of magnetorheological [13][14][15][16] and the electrorheological materials [17], which can change the stiffness or Young's modulus under magnetic field variations and achieve vibration control in a specific frequency range. In [18], a negative stiffness seat suspension system combined with a pneumatic spring and stiffness control mechanism was proposed, and the related control algorithm that affects device stiffness variations associated with position and velocity data evaluation was designed.…”

“…In terms of structure, in addition to traditional shock absorbers, semiactive seat suspensions have also been designed in different styles. Bai et al (2017) [14] designed an integrated semiactive seat suspension that included a swing mechanism ( Figure 3) that converts longitudinal and vertical motion into rotational motion and a torque-controlled rotary magnetorheological (MR) damper operated in a pure shear mode to attenuate vertical and longitudinal vibrations. [20] proposed a new semiactive seat suspension based on the variable admittance (VA) concept and designed a rotating VA device based on the MR damper.…”

Research on semi-active vibration isolation system based on electromagnetic spring

“…Vibration isolation technology is the most widely applied in the field of vibration control, and it has a wide range of applications in the field of civil engineering, aerospace, automobile, ships and precision manufacturing and processing, etc. Vibration isolation is generally categorized as passive, active and semi-active vibration isolation [1][2][3][4]. Passive vibration isolation is widely employed to structural vibration isolation because of its simple structure, low power consumption, high stability, etc.…”