Acoustic Detection of Vehicles Outside the Field of View at Intersections
-Influence of Oncoming and Preceding Vehicles-

Masao Ishihama (Ishihamagiken Consulting)

To prevent head-on collisions at intersections, we estimated the capability of a method that uses a microphone array placed across the entire front of a vehicle to selectively detect the main component of tire noise from the intersection corner, which obstructs the field of view, from among the incoming sounds using beamforming and signal processing. As a result, we confirmed the possibility of distinguishing between oncoming vehicles, vehicles passing on intersecting roads, and vehicles approaching from blind spots.

Determining Stabilization Parameters in the Inverse Matrix TPA
-Part 1: Validation with Road Noise-

Hiroshi Kashiwazaki･Makoto Takeshita･Zhiqiang Weng･Michio Murase (Ono Sokki)

In the matrix inverse method of Transfer Path Analysis (TPA), a stabilized approximate inverse matrix is often used to suppress the effects of measurement error. However, the optimal parameters for stabilization vary depending on the test object and frequency, and its manual tuning requires time and effort. This presentation reports on the development of an automatic determination method for the stabilization parameter and its validation using suspension inputs of road noise on an actual vehicle.

Method for Determining Measurement Points for Virtual Point Transformation

Makoto Takeshita･Hiroshi Kashiwazaki (Ono Sokki)

In performing Virtual Point Transformation (VPT), it's necessary to consider the stiffness of the mounting locations and the stability of the transformation matrix when determining the measurement positions. However, manually selecting these positions from a large number of combinations is time-consuming and labor-intensive. Therefore, this presentation will introduce an algorithm developed to automatically determine the measurement point locations, and we will confirm its effectiveness through experiments on an actual vehicle.

Development of a Multi-Physics Simultaneous Measurement and Visualization System for Wide-Area and Transient Acoustic Phenomena

TAKEO BAN･YUTO FURUSAWA (DAIHATSU MOTOR)･OSAMU TERASHIMA (GIFU UNIVERSITY)･TOYA MAKINO (TOYAMA Prefectural University)･HIROTO TAKEHARA (GIFU UNIVERSITY)

Identifying the factors behind wide-area and transient acoustic phenomena that cause discomfort to vehicle occupants has long been a challenge. In this study, we developed the world's first simultaneous measurement system featuring a 12-channel acoustic probe array. We designed the requirement specifications and commissioned its fabrication to a specialized vendor. This system enabled synchronous measurement of three-dimensional acoustic intensity vectors and airflow velocity within HVAC duct noise. Through coupled data analysis, we quantitatively visualized spatiotemporal noise fluctuations, providing valuable insights into complex acoustic phenomena.

Vehicle Body Structure Design Method for Low-Frequency NV phenomenon in Early Development Stage Using Component Mode Analysis

Shinichi Kaji･Akihiko Katagiri (Honda Motor)･Moe Hanashima (ESTECH Corporation)･Narikuni Seiya (Honda Motor)

This study proposes a method for developing vehicle body structures to address low-frequency NV phenomena in the early design phase. Component mode analysis is used to define subsystem targets with ranges based on system goals. A CAE model created from early-stage information is employed to evaluate structures before initial drawings are issued, and the results are reflected in the design to improve drawing quality.