Lyd til elbiler Store Støjdag 29. oktober 2012 Torben Holm Pedersen SenseLab, DELTA, Denmark thp@delta.dk 1
NHTSA sept. 2009 The HEV was two times more likely to be involved in a pedestrian crash when a vehicle is slowing or stopping, backing up, or entering or leaving a parking space (a statistically significant effect was found). Incidence rate of pedestrian crashes in scenarios when vehicles make a turn was significantly higher for HEVs when compared to ICE vehicles. The incidence rate of bicyclist crashes involving HEVs was significantly higher when compared to ICE vehicles at very low speed such as when vehicles are turning, slowing, or stopping, backing nup, or entering or leaving a parking space, On a roadway was the most common location of bicyclist crashes involving both HEVs and ICE vehicles with no statistically significant difference. Bicyclist crashes involving HEVs at intersections or interchanges were significantly higher when compared to ICE vehicles. Are vehicles driven in electric mode so quiet that they need acoustic warning signals? Ulf Sandberg et. al. ICA 20 It is concluded that already a significant number of our present internal combustion engine vehicles are so quiet at low speeds that normally one cannot hear any difference between an electric and a normal vehicle in an urban area. Tyre/road noise is the dominating noise in most cases where a light vehicle is driven at speeds at or above 15-20 km/h (heavy accelerations are the exceptions), and this is the same whether the vehicle is electric or not. Thus, it is a property of our vehicle fleet which we have had for more than a decade, and few have considered that as a safety problem. Therefore, there is not enough justification for equipping our future quiet vehicles with extra artificial noise or warning sounds. Holland 20 Hybrid- og elbiler er meget stille under 20 km/t Over 30 km/t er dækstøjen dominerende I byer vil fuld overgang til hybridbiler betyde 1-3 db mindre støj I byer vil fuld overgang til elbiler betyde 3-4 db mindre støj En fuldstændig overgang vil ikke ske før 2030 2
www.madebydelta.com Målinger af biler og baggrundsstøj Forsøg med reaktionstider med blinde Blindes adfærd i trafikken stoler ikke på hørelsen i høj baggrundsstøj Lyd fra køretøjer er den mest effektive advarsel Standardisering ISO/TC 43/SC 1 N 1798-ISO/TC 22 N 2929: "Measurement of minimum noise emitted by road vehicles SAE International J2889-1, EITSSHF1 Vehicle Sound for Pedestrians : "Measurement of minimum noise emitted by road vehicles 3
Japans trafikministerium Guideline Januar 20 For biler uden aktiv forbrændingsmotor En advarselsanordning som genererer lyd fra start til 20 km/t og under bakning Pause switch Midlertidig afbrydelse af signalet er tilladt med en afbryder, som ikke kan fastlåses Føreren skal tydeligt kunne se, når denne er aktiveret Japan Januar 20 Lydkarakter og lydstyrke Lyden skal opfattes som kommende fra et køretøj Lyden skal ikke være: Sirener, klokker eller melodier Horn Lyde fra dyr f.eks. fra insekter eller fuglesang Lyde fra naturfænomener som bølger, vind, floder, bække osv. Lyde som ud fra en sund fornuft ikke kan stamme fra et motorkøretøj Lyden skal ændres i styrke eller frekvens afhængig af køretøjets hastighed Lydstyrken skal ikke overstige niveauer fra biler med forbrændingsmotor ved 20 km/t Retningslinjerne skal revideres, når den teknologiske udvikling etc. kræver det Flere signaler Sound Driving mode Speakers Duration / condition Message Start sound Turning power on Front + Rear 1-2 sec. Active car near by Idle sound* When speeder is activated. Front when in forward. Rear when in reverse Speed 0-5 km/h Car beginning to drive Drive sound Speed above 5 km/h Front when in forward. Rear when in reverse Speed 5-30 km/h Driving car Reverse sound When speeder is activated Rear when in reverse Speed 0-30 km/h Backing car * Samme som laveste Drive sound 4
Krav til lydkarakter Hørbar Lige så hørbar som en bil med forbrændingsmotor Passende Man skal intuitivt forbinde lyden med et køretøj Ikke generende Mindst mulig generende for naboerne Normal hearing thresholds and equal loudness curves from ISO 226 200 Hz 7000 Hz Average hearing thresholds for different age groups (males) according to ISO 7029 0-5 - Hearing loss, db -15-20 -25-30 -35 30 years 50 years 70 years -40 125 250 500 00 2000 4000 8000 Frequency, Hz Max 2000 Hz 5
Støjbetinget høretab Max 00 Hz Noise induced hearing loss (ISO 1999) Max 00 Hz Torben Holm Pedersen Baggrundsstøjspektre 80 70 60 50 40 30 20 12.5 16 20 25 31.5 40 50 63 80 0 125 160 200 250 315 400 500 630 800 1k 1.25k 1.6k 2k 2.5k 3.15k 4k 5k 6.3k 8k k 12.5k 16k 20k Sound pressure level, db re 20 µpa Central Copenhagen 64 db(a) Suburb 1, north of Cph. 60 db(a) Eastern outskirts of Cph, 55 db(a) Suburb 2, north of Cph. 50 db(a) Village 35 db(a) Frequency, Hz 200 Hz 6
Lydudbredelse Med- og modvind - 200 m Uden skærm Med 3 m skærm Sound pressure level Sound pressure level 5 5 Hårdt terræn 0-5 - -15-20 -25 0-5 - -15-20 -25 32 63 125 250 500 1k 2k 4k 8k 32 63 125 250 500 1k 2k 4k 8k Sound pressure level Sound pressure level 5 5 Blødt terræn 0-5 - -15-20 -25 0-5 - -15-20 -25 32 63 125 250 500 1k 2k 4k 8k 32 63 125 250 500 1k 2k 4k 8k 200 Hz 200 Hz Lydisolation Idealized sound reduction index 60 55 50 45 40 db 35 30 25 20 15 200 Hz I II III IV V Idealized sound reduction indices for different types of window constructions: I: Old window with 3-4 mm panes (one layer only) II: New window with 4-15-4 mm IGU s (insulating glass units) III:Fixed frame with laminated panes IV: Coupled sashes with sound insulating IGU s on one side V: Deep window with separate sashes and sound absorbing lining in between Primære frekvensområde 200-00 Hz 0-5 km/h: Stationary frequency f = f Idle f Idle Above 5 km/h: f = v 5 7
Målinger Maksimalniveauer 2 m 80 1. gear 2. gear 3. gear Sound Pressure Level, db(a) 70 60 50 Total vehicle noise Engine noise calc. from RPM Engine noise calc. from SPL diff. Tyre noise 40 0 5 15 20 25 30 35 40 45 Speed, km/h Niveauændring af advarselslyd 80 Relative Sound Pressure Level, db 70 60 50 Level with same audibility as ICE car 40 0 20 30 40 Speed, km/h 8
Test method for equal audibility in background noise Simplificeret baggrundsstøj 55 db(a) Simplified background noise spectrum, max = 0 db 0 Sound pressure level, db re 20 µpa - -20-30 -40-50 20 25.5 40 50 63 80 00 25 60 00 50 15 00 00 30 00 1k 5k 6k 2k 5k 5k 4k 5k 3k 8k Bestemmelse niveau for 50% detektion 0 80 Detection precentage 60 40 20 0-15 - -5 0 5 15 Level re. prelim. threshold, db 9
Niveauer med samme hørbarhed Threshold level LAeq signal(pd50%) LAeq, db Same audibility as real reference car dbalice LAeq, db Driving Jet4low Low friction Mitsu 1160 rpm Natural hum Q4noise Reverse Rev Acoustic one Rev Electro bell Rev Electro ping Rev Mitsu Rev Up tones 36.4 54.1 36.5 54.2 42.4 60.2 37.8 55.5 40.5 58.2 36.5 54.2 32.0 49.7 34.1 51.8 37.9 55.7 34.8 52.5 Audibility Level as an Internal Combustion Engine Mere end db forskel Krav til lydkarakter Hørbar Lige så hørbar som en bil med forbrændingsmotor Passende Man skal intuitivt forbinde lyden med et køretøj Ikke generende Mindst mulig generende for naboerne
Suitability listening test - Instruction Your task is to assess how suitable the sounds are for an electric car. I.e. how well the sound fits the car shown in the picture. The sounds you will be listening to are constant, but when the car is driving, the sound will vary as the motor sound from normal cars. Suitability listening test Annoyance listening test - Instruction Imagine that you hear these sounds at home as part of the traffic noise. The sounds are neither more neither less prominent than the motor sound from the normal cars. The sounds you will be listening to are constant, but when the car is driving, the sound will vary as the motor sound from normal cars. Your task is to assess the annoyance of the sounds 11
Annoyance listening test Test results Drive sounds Suitability Annoyance Extremely Very Moderately Slightly Not at all. Q4noise Mitsu 1156 rpm Big truck Emission free Jet4low Low friction Natural hum Motorgear N clean Q4noise Mitsu 1156 rpm Big truck Emission free Jet4low Low friction Natural hum Motorgear N clean Test results Reverse sounds Suitability Annoyance Extremely Very Moderately Slightly Not at all. Rev Up tones Rev Mitsu Rev1 P-like Rev2 P-like Rev3 P-like Rev Electro Bell Rev Electro ping Rev Acoustic one Rev Pulse Choir Rev Up tones Rev Mitsu Rev1 P-like Rev2 P-like Rev3 P-like Rev Electro Bell Rev Electro ping Rev Acoustic one Rev Pulse Choir 12
Directional characteristics Relative db FC FP/FP RP/RP RC Front speaker(s) 0-3 -8 <-12 Rear speaker(s) <-12-8 -3 0 Torben Holm Pedersen Optimale lyde + gode lydsystemer => mindre støjforurening end nu Lydene sendes kun ud i kørselsretningen Ingen konstant tomgangslyd Ingen lyd over 25 km/t Niveauer begrænset til samme hørbarhed Ingen lavfrekvente lyde * *Aliance of Automobile manufactures 13
Thank you for your attention! 14