Indoor pass-by testing delivers an extremely robust and repeatable testing approach that eliminates external noise interference within the controlled environment of a semi-anechoic chamber. Unlike conventional pass-by measurements where the test vehicle drives past two fixed microphones, indoor pass-by testing arranges an array of microphones alongside the vehicle running on a chassis dynamometer, with the vehicle accelerated following the same procedures as traditional outdoor pass-by tests.

ISO 362-3 governs the measurement of noise emitted by accelerating road vehicles. Recent updates to this ISO standard help guarantee consistent testing results for the latest vehicle models. At present, official external noise measurements for type approval complying with the prevailing ISO 362-1 standard must be performed on certified outdoor test tracks. Subject to environmental disturbances, these conventional test sites fail to meet the consistency requirements arising from the automotive industry’s growing testing demands. Vehicle noise should be measured under controlled conditions free from weather and other ambient interferences.

ISO 362-3:2016 specifies requirements for test facilities to achieve accuracy equivalent to that of certified type-approval test tracks, enabling indoor testing of M and N category vehicles as stipulated in Part 3 – Indoor Testing.

ISO 16254:2016 specifies the engineering method for measuring noise emitted by M and N category road vehicles at standstill and low-speed operation. With the advancement of electric vehicles, their ultra-low noise levels pose hazards to pedestrian safety.

ISO 16254:2016 establishes a method to measure the minimum noise emissions of road vehicles and quantify the performance of any external sound generation systems installed to acoustically signal vehicle approach, presence and/or departure to nearby pedestrians.

All pass-by anechoic chambers developed by Landtop Technology comply with the latest drafts of the above standards, supporting both noise measurement of accelerating vehicles and minimum noise emission testing.

Landtop Technology has designed numerous semi-anechoic pass-by chambers for domestic automobile manufacturers, delivering optimal solutions to build qualified testing environments.

Xiangfan Test Center Pass-by Noise Anechoic Chamber

Xiangfan Test Center Pass-by Noise Anechoic Chamber

■ Automotive Industry