Development of pitch vibration reduction control for vehicles using band-stop filters

Yuma Matsumoto (Toyota Motor)

Vehicle pitch vibration generated when the drivetrain produces driving force poses a ride comfort challenge. This study proposes a control strategy that applies a band-stop filter to the driving force to reduce pitch vibration while minimizing the filter's impact on perceived acceleration. Simulation and real-vehicle verification results are reported.

Basic Study on Vibration and Impact During Vehicle Operation and Transportation: Part 1
-Theoretical Discussion of Impact During Transportation-

Hiroshi Uchida (Trans Quality Research organigation)

Vehicles are used on a variety of roads, surfaces, and in various work sites. Understanding and analyzing vibration and shock during actual driving is important and broad, involving fields such as fracture and reliability, and covers a wide range of fields, from transportation to space and energy, precision electronics, and life sciences. However, there are challenges in measurement, testing, standards and ,application. Previous reports have linked vibration to cargo damping and genetic analysis. This report begins with the discussion of shock.

Pitch Damping Integrated Control Considering Control Device Characteristics for Compatibility of Acceleration Feeling and Ride Comfort

Takuma Takeuchi･Yuma Matsumoto (Toyota Motor)

The increased responsiveness of driving force due to electrification tends to increase pitch speed, which rebels against the feeling of acceleration. Increasing pitch damping can improve the feeling of acceleration, but measures using shock absorbers alone are bad for ride comfort. In this study, we propose integrated pitch damping control that considers the characteristics of the drive actuator and semi-active suspension to achieve both a feeling of acceleration and ride comfort.

Effect of pitch damping moment due to internal torque in propeller shaft-type AWD

Shinya Konishi･Shingo Koumura (Toyota Motor)

Analysis of pitch motion in propeller shaft AWD systems in response to road input was conducted using a 5-DOF (Z, q, X, w1, w2) model. Differences in the suspension trajectories of the front and rear wheels generate pitch damping moments due to internal torques. The aforementioned effect was verified both computationally and experimentally, showing that pitch motion is reduced in AWD vehicles compared to 2WD vehicles.

Verification of Driver Delay Time (τ_L) Caused by Human Stimuli Using a Vibrator

TOMOYA KATO･TETSUHIRO OKUDA (TOYOTA BOSHOKU)

Driving operability is an important performance factor in the domain of vehicle handling. To develop seats that make drivers feel comfortable and contribute to the overall improvement of vehicle performance, various evaluations are being conducted. In this study, we use a vibrator embedded in the seat to provide prior alerts and quantitatively assess the impact on the vehicle's response characteristics by evaluating steering behavior using the first-order delay parameter (τ_L) of the driver model.

Rig-Based Investigation of R&H Performance Variations in PBV Rear Semi-Trailing Arm Suspension due to Specification Changes

SEONGHUN KIM･SEUNGMIN KWON･DAVID P. SONG･JONGHO KO･YONGSUB YI･JOOMIN JANG･TAEHUN KO (Hyundai Motor)

This study investigates the ride and handling(R&H) characteristics of semi-trailing arm rear suspension through module-level rig testing. Kinematics and compliance(K&C), comfort roadway(CRW), and cleat impact tests were conducted to assess the effects of two design changes: bushing stiffness reduction and damper repositioning. The results show that reduced bushing stiffness lowered lateral stiffness, while damper repositioning altered the load distribution, increasing vertical loads on the damper and reducing load concentration on the bushings. These findings provide a foundation for suspension tuning prior to full-vehicle testing and highlight the importance of system- and component-level optimization in achieving target ride comfort.