This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Experimental Investigation of Dither Control on Effective Braking Torque
Technical Paper
2003-01-1617
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
Automotive brake squeal is a problem that has plagued the automotive industry for years. Many noise cancellation techniques have been published. One such technique is the use of an external dither signal, that has been shown to suppress automotive disc brake squeal in experiments with a brake dynamometer, but the effect of this control on the system's braking torque has yet to be determined. By imposing a high frequency disturbance normally into the brake pad, squeal is suppressed. There are many studies that lead to the conclusion of a lower effective braking torque due to the high frequency dither control signal. Under the assumption of Hertzian contact stiffness it has been speculated that the loss in braking torque is due to a lowering of the average normal force. There has also been work done that proves that the application of a dither signal in the normal direction eliminates the ‘stick-slip’ oscillation that causes brake squeal by an effective decrease in the friction force. Yet another theory indicates that the effective contact area is reduced causing a lowering of the mean coefficient of friction. It is not apparent whether any of these models accurately portrays the interaction of the brake pads and brake rotor. This paper will examine the effect of normal dither control on the effective braking torque using a brake dynamometer. A dither control signal of 23 kilohertz with several force amplitudes are examined. A statistically significant reduction in the braking torque has been found that is directly related to the amplitude of the dither signal applied. These tests were repeated at varied brake pressure to prove that the results were not dependent on the specific braking conditions used.
Recommended Content
Authors
Citation
Badertscher, J. and Cunefare, K., "Experimental Investigation of Dither Control on Effective Braking Torque," SAE Technical Paper 2003-01-1617, 2003, https://doi.org/10.4271/2003-01-1617.Also In
References
- Kinkaid N. M. Papadopoulos P. Automotive Disc Brake Squeal: A Review Journal of Sound and Vibration 2002
- Graf, A. Active Control of Automotive Disc Brake Rotor Squeal Using Dither 2000 The Georgia Institute of Technology
- Mills, H.R. Brake Squeak 1938 Institution of Automobile Engineers
- Holubecki, R.A.C.F.Z. Interim report on disc brake squeal 1959 Motor Industry Research Association Warwickshire, England
- Sinclair, D. Frictional Vibrations 1955 Trans. ASME Journal of Applied Mechanics , 207 213
- Spurr, R.T. A theory of brake squeal 1961 Proc. Auto. Div. Instn. Mech. Engrs. 33 52
- North, M.R. Disc Brake squeal - a theoretical model 1972 Motor Industry Research Association Wawickshire, England
- Baba H. Study on reduction of brake squeal caused by in-plane vibration on rotor 2001 SAE Warrendale, PA
- Hess, D.P. Soom A. Normal Vibrations and Friction Under Harmonic Loads: Part I- Hertzian Contacts ASME Journal of Tribology 1991 113 January 80 086
- Hess, D.P. Soom A. Normal Vibrations and Friction Under Harmonic Loads: Part II- Rough Planar Contacts ASME Journal of Tribology 1991 113 January 87 92
- Hess, D.P. Soom A. Kim C.H. Normal Vibrations and Friction at a Hertzian Contact Under Random Excitation: Theory and Experiment Journal of Sound and Vibration 1991 153 3 491 508
- Oden, J.T. Martins J.A.C. Models and Computational Methods for Dynamic Friction Phenomena Computer Methods in Applied Mechanics and Engineering 1985 52 1-3 527 634
- Ferri, A. A. Friction Damping and Isolation Systems ASME Journal of Vibration and Acoustics 1995 117B June 196 206