An active force cancellation system for noise reduction could be on the roads soon following a decade of development
The system uses actuators near mount attachment points to generate waves at the same frequency and amplitude as those created by noise and vibrations that are 180° out of phase with the original. The actuators are driven in a closed feed forward control loop, which means multiple order harmonic waves are cancelled even when engine speeds change quickly.
“It sounds simple, but we have been working on it for more than a decade,” says Manfred Hofmann, technical director at Trelleborg Automotive’s Technical Centre in Höhr-Grenzhausen, Germany.
Trelleborg is talking to OEMs and offering the active force cancellation system as an alternative to balance shafts. “Use of balance shafts is quite expensive technology and it mainly works for higher RPMs, so we’re suggesting manufacturers opt for an active system instead, which offers wider performance,” says Hofmann.
Trelleborg is also looking to target specific vehicles. “Some vehicles, such as three-cylinder diesels, have greater need for such technology,” says Hofmann. “Rather than being fitted as standard, active force cancellation systems could be ideal for those cars whose engines create more vibration than others.”
And one major manufacturer has enquired about its use in a project to create the perfect engine sound.
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