Study at TCU


Name SAKURAI Toshiaki
Official Title Associate Professor
Affiliation Mechanical Engineering, Science and Engineering
Profile My research area of expertise is the presentation of load transfer modes in elastic structures and occupant safety in terms of vehicle body structure in collision phenomena.
For thin-walled structures such as passenger cars, body structures have been designed with load transmission in mind as a concept, but there are few methods for quantitative evaluation. Currently, strength calculation is possible by computer simulation, and complex shapes that meet performance goals can be calculated by structural optimization. On the other hand, there are many parts that rely on the intuition of the designer for the first shape that should be the basis of the design, and the concept is conscious of load transmission. By making it possible to quantitatively evaluate the load transmission, it is possible to propose a rational basic shape, and then proceed with the optimization calculation to efficiently reach the target shape. It will be a necessary technology for automobiles today, which requires transition to electric vehicles and cost reduction ever before.
In addition, the number of vehicles as city commuter vehicles represented by minicars (microcars) is increasing due to market demands and the perspective of environmental issues. Many of these vehicles tend to be lighter and have less occupant survival space than regular passenger cars. Collision safety is a regulation that protects the lives of occupants and is an important performance that maintains a comfortable motorized society. By improving the structure of the vehicle during a collision to a structure that can efficiently absorb collision energy while suppressing deformation, it is possible to reduce the burden on the occupants during a collision.
Research Field(Keyword & Summary)
  1. (1) Load Transfer

    The concept is that the load applied during the structure is transmitted from the load point to the support point while being transmitted through the highly rigid part. In ancient times, it was also used in the concept of structural design of aircraft, and it is a concept that is often used when designing passenger cars, and most of them are considered in terms of the direction of principal stress.

  2. (2) Computer Aided Engineering (CAE)

    A method of performing structural analysis by computer simulation. Many use the finite element method to calculate the deformation and stress of a structure when a static or dynamic load is applied to the structure. The optimization calculation can be performed by setting the objective function and performing the iterative calculation.

  3. (3) Collision Safety

    Evaluate vehicle collision safety based on the degree of occupant injury. The standard changes depending on the collision direction and speed. Highest required performance and high priority in vehicle design. Many collision safety designs require both high rigidity of the cabin structure and a structure that can absorb collision energy.

Representative Papers
  1. (1) Elucidation of brake discontinuation mechanism in rear-end collision, Journal of the Japanese Council of Traffic Science 19(2), 13-25, 2019
  2. (2) Development of Pedestrian New Legform Impactor aPLI using Scale Model, International Conference on Advanced Technology in Experimental Mechanics 2019, The Asian Conference on Experimental Mechanics 2019
  3. (3) Prediction of Cervical Injuries in Fall Accidents Based on Autopsy Findings, Japanese journal of occupational medicine and traumatology 67(2), 108-113, 2019
  4. (4) Development of fast computation algorithm for load transfer Ustar (U*) calculation in structures with slidable supports, Transactions of the Japan Society of Mechanical Engineers 85(870), 18-00374-18-00374, 2019
  5. (5) Development of Theoretical Prediction Method Using Ustar (U*) for Stiffening Effect of Structures and Application to Determination of Stiffener Location for Passenger Car Bodies under Rapid Steering, Transactions of the Society of Automotive Engineers of Japan 49(6), 1243-1248, 2018
  6. (6) Optimization of Vehicle Body Local Structure Using Load Transfer Ustar (U*) Calculation, Transactions of the Society of Automotive Engineers of Japan 49(6), 1249-1254, 2018
  7. (7) Study of vehicle speed estimation in traffic accidents related to a scooter type wheelchair with multi-body simulation, 26th Annual Congress of the European Association for Accident Research and Analysis,pp.147-156,2017
  8. (8) Study on estimation of vehicle collision speed in the case of vehicle collision with guard-pipe, Journal of the Japanese Council of Traffic Science 16(1), 18-26, 2017
  9. (9) Effectiveness of a post-crash braking system in rear-end collisions in Japan, 7th International Conference on ESAR "Expert Symposium on Accident Research",CD-ROM, June 2016
  10. (10) Study of injury mechanism of far-side occupant in K-car side collision, Journal of the Japanese Council of Traffic Science 14(3), 15-25, 2014
  1. 2007-542832
  2. 2011-066191
  3. 2013-131205
Grant-in-Aid for Scientific Research Support: Japan Society for Promotion of Science (JSPS)
Recruitment of research assistant(s) No
Affiliated academic society (Membership type) JSAE (regular member), JSME (regular member)
Education Field (Undergraduate level) Body structure, Collision safety, Occupant Safety
Education Field (Graduate level) Body structure, Collision safety