Hiroto Ido (Chuo Univ., ex-Toyota CRDL, Sony) Delivers Keynote at NV Analysis Seminar in Nagoya

Newton Works Corporation (Headquarters: Chuo-ku, Tokyo, President & CEO: Toshikazu Yamanashi) held a seminar titled "Evaluation Metrics for Noise and Vibration (NV) Analysis and Their Practical Applications" in Nagoya on June 5, 2026. The event was targeted at design and CAE engineers facing NV challenges, focusing on the practical application of NV analysis.

Scene from the NV Analysis Seminar (Nagoya Venue)

Keynote Speech: Identifying Causes Through Evaluation Metrics

The keynote was delivered by Hiroto Ido, who previously worked on NV analysis at Toyota Central R&D Labs and Sony, and currently serves as a joint researcher at Chuo University. He provided a systematic explanation of technologies ranging from cause identification of NV problems to the verification of consistency between analysis and experiments, and optimal design.

Hiroto Ido from Chuo University delivering the keynote

Ido explained the importance of separating "input" and "transfer characteristics" as the essence of NV problems. He pointed out that the sound pressure observed in actual products is a mixture of these factors and changes depending on the input, meaning simple comparisons of measured values often fail to identify the root cause.

Therefore, he demonstrated the importance of excitation experiments and transfer functions as an approach to properly isolate factors and evaluate the "transfer system," such as shapes and material (medium) characteristics that designers can control. He introduced methods utilizing the following evaluation metrics in design practice:

- Acoustic Intensity and Acoustic Power
- Acoustic Radiation Efficiency
- Contribution from Vibration to Sound

The lecture explained phenomena such as sounds canceling each other out due to the complex distribution and phase of vibration on the structural surface. He demonstrated the effectiveness of approaches that consider not only the magnitude of simple vibrations but also the phase and radiation efficiency.

Furthermore, he mentioned the "reliability of experimental data" to ensure the accuracy of the analysis. He presented signal processing techniques (such as the Cross-Spectrum method, various window functions, and Overlap processing) for noise reduction in actual measurements. Additionally, he touched upon the evaluation of measurement data using the "Hilbert transform" to check system nonlinearity, indicating that handling measurement values based on correct signal processing knowledge is essential for verifying consistency between CAE and experiments.

Is Structural Optimization Truly Useful for NV Countermeasures?

Ikarimoto from the Newton Works CAE Comprehensive Development Center verified and reported on whether structural optimization is useful for NV countermeasures. The background to this is that while "non-parametric shape optimization" is theoretically known to have extremely high effects in reducing Noise and Vibration (NV), there have been customer voices asking, "I understand optimization is effective, but are there cases verified on actual machines?" "How much effect is actually produced?" and "Isn't it difficult to manufacture optimized complex shapes as they are?" Also, from the standpoint of a CAE engineer, there was a strong desire to "not only see simulation results but actually make and verify things," "check the effects by handling the optimized shape directly," and "challenge manufacturing utilizing 3D printers," which led to this initiative.

In this verification, non-parametric shape optimization was performed using "OPTISHAPE-TS" developed by Quint Corporation. First, a comparison was made between the experimental results and analysis results of the basic shape produced by a metal 3D printer to confirm its validity. After that, based on the optimized shape, experimental samples were similarly produced with a metal 3D printer. Finally, a physical machine comparison was made between the basic shape before optimization and the shape after optimization, reporting on the specific effects.

Optimization results produced by computer simulation and test pieces reproduced by a 3D printer

NV Optimization Across the Entire System

Sasaki from the Newton Works CAE Comprehensive Development Center explained NV analysis methods targeting rotating machinery systems. Using an integrated model of bearings, shafts, gears, and cases employing the bearing design calculation tool MESYS developed by MESYS AG of Switzerland, an analysis considering the mutual influence of each element was conducted. He introduced vibration and noise reduction methods through design improvements such as:

- Gear tooth flank shape optimization
- Case shape optimization

Excerpt from Sasaki's presentation materials

Summary

In this seminar, a series of processes were systematically presented:

- "Cause identification through evaluation metrics"
- "Ensuring consistency between experiment and analysis"
- "Optimal design for the entire system"

In particular, centered around Mr. Ido's lecture, the approach of thinking about NV problems by dividing them into input and transfer characteristics was shared among all attendees, becoming a guideline for utilizing analysis in the design field.

Seminars Held Here
Newton Works holds many CAE seminars related to NV. Please check below for the latest information.

Seminar Information Here

Speaker Introduction: Who is Hiroto Ido?
He is a specialist who has consistently been at the forefront of vibration and noise analysis and acoustic numerical simulation (BEM/FEM) since his student days. Building his career at Toyota Central R&D Labs and Sony, he has supported the design and development of innovative products such as AIBO and VAIO. He currently serves as a lecturer at the Japan Modal Analysis Conference (JMAC), a joint researcher at the Faculty of Science and Engineering at Chuo University, and a part-time director at Quint Corporation. He is a specialist in vibration and noise analysis with solid theory cultivated over many years and extensive practical experience in "manufacturing" at major manufacturers.

What is MESYS?
It is a design and technical calculation software (1D CAE tool) specialized for mechanical elements (mainly bearings, shafts, gears, etc.) developed by MESYS AG in Switzerland. It is widely used globally among engineers designing "rotating machinery" in fields such as automotive, machine tools, wind power generation, robotics, and general industrial machinery. Calculating precisely down to the movement of internal balls and rollers of a bearing using general 3D CAE (Finite Element Method: FEM) would take an enormous amount of calculation time (hours to days).
However, because MESYS is based primarily on "theoretical calculation (formula-based)," it can calculate accurate bearing characteristics and lifespan at an overwhelming speed of just seconds to minutes. Therefore, it is highly suitable for quickly comparing and considering various combinations (parameter studies) of "which bearings to use and how to arrange them" in the early stages of design.

Details on MESYS Here

What is OPTISHAPE-TS?
It is a world-class structural optimization software developed by Quint Corporation. Utilizing various methods such as topology optimization, non-parametric shape optimization, and bead optimization, it automatically derives the "ideal shape" based on mathematical grounds to maximize product rigidity, control natural frequencies, and achieve weight reduction. Its control functions that can consider the precise manufacturing requirements unique to Japanese manufacturing have gained extremely high trust from engineers in a wide range of fields such as automotive, aerospace, precision instruments, and construction machinery.

Details on OPTISHAPE-TS Here

What is Newton Works Corporation?
An independent engineering solutions provider supporting the manufacturing industry with advanced technological capabilities, placing mechanical CAE (Computer Aided Engineering) at the core of its business.