Approach to Automotive Disc Brake Hot Judder due to Thermal Elasticity from the Viewpoint of Self-Excited Vibration

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K18042
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Dynamics/Control
• Research Institution: Oita University
• Principal Investigator: NAKAE TAKASHI 大分大学, 理工学部, 准教授 (80579730)
• Research Collaborator: Ryu Takahiro
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 自励振動 / ディスクブレーキ / 熱変形 / 時間遅れ / パターン形成 / ジャダー / 摩擦振動 / 安定性

Outline of Final Research Achievements

In high-speed areas of highways and roads with steep descents, the heat in car disc brakes sometimes causes a vibration problem. The generation mechanism of hot judder caused by thermal deformation in disc brakes was clarified. Fluctuation of the contact force between the disc and pad due to vibration of the brake system causes fluctuation of the disc surface temperature, and fluctuation of the temperature causes larger fluctuation of the contact force in one rotation of the disc with time delay. It is concluded that hot spots and hot judder are excited by self-excited vibration with time delay.

Free Research Field

機械力学

Academic Significance and Societal Importance of the Research Achievements

従来の摩擦自励振動系には見られない，熱に起因する変形形状のフィードバックによる時間遅れ系の自励振動を解明することができた。これは，摩擦に関連した新たな自励振動分野の確立への第一歩となる。これからの日本の自動車業界の技術の信頼性，安全性，快適性をさらに高めるものと確信している。また，この技術は自動車業界のみならず，鉄道，航空・宇宙産業など広い分野で有用性がある。