Optimal design of passenger vehicle seat with the use of negative stiffness elements

Abstract

A seat that provides good vibration isolation is of prime importance for passenger’s safety and health. The main conflict in seat suspensions implies that the increasing initial deformation of the system (increase in “static discomfort”) leads to better isolation of accelerations (increase in “dynamic comfort”). Many researchers have focused on overcoming or at least suppressing this conflict between load support capacity and vibration isolation by modeling new suspension systems, such as the so-called negative suspension systems. However, apart from the modeling of new suspension systems, optimization is an important part in designing a seat and finding the best compromise between these two objectives. Thus, in this work, four types of seat suspension systems with embedded negative stiffness elements are implemented and optimized in order to be benchmarked. Three of them have already been tested either in passenger or in an off-road vehicle seat. All the vibration isolators are optimized with genetic algorithms in respect to static and dynamic factors of ride comfort by applying constraints oriented to the objectives and the design of the structure. The optimization is implemented for two excitations, which correspond to a vehicle driving over road profiles of Classes A and B, and the common solutions are outlined.

Fundamentals of Motion Planning for Mitigating Motion Sickness in Automated Vehicles

“…In particular, recent research have focused on providing solutions to mitigate motion sickness with ideas from the field of human factors and ergonomics, interior design, and automotive engineering. In addition, regarding ergonomics, research has focused into seat design [12] and their arrangement [13], active head-tilting [14], cabin lighting, vection (illusion of self-motion) and passenger biometric data collection [15]. In terms of vehicle dynamics, few researchers have focused on comfort from the view of braking control [16], suspension design [17], and adaptive cruise control [18], but limited work has been done in motion planning for vehicle control in terms of motion sickness minimization.…”

Vibration reduction performance of an innovative vehicle seat with a vibration absorber and variable damping cushion

“…Based on Papaioannou et al, 47 Papaioannou proposed the NSS4 scheme, in which a vibration absorber with the optimal parameters is installed under the vehicle seat, to reduce the vibration response and improve the vehicle comfort. First, according to this idea, this section designs a passive vibration absorber with the optimal vibration reduction performance parameters to reduce the vibration response, 48–50 and its basic principle and structure are shown in Figure 13.…”

Investigation of Seat Suspensions with Embedded Negative Stiffness Elements for Isolating Bus Users’ Whole-Body Vibrations

“…KDamper is a passive suspension combining appropriate stiffness elements and a negative stiffness (NSS) element, which has been applied in seats in the latest work of Papaioannou et al [29] and is described extensively. The K-Seat (Figure 4) consists of the total seat mass (𝑚 𝑠𝑒 ) which is supported by two parallel linear springs (KS and Kv) and a damper (Cv).…”

“…A new type of seat suspension with a hollow composite rubber spring was developed [28], which can attenuate more effectively the low frequency from the uneven ground, and provide simultaneously a more stable support so that the driver can control the vehicle effectively. Recently, a novel vibration isolator (KDamper) was introduced in passenger vehicle seat [29], [30]. The novel seat suspension was benchmarked with the most common seat models in the literature and was proven to be superior in various types of analysis (comparison of optimized solutions, varying road input and passenger mass, investigation of seat-to-head transmissibility etc.…”