This paper describes the evaluation of the annoyance and suitability of a back-up warning sound for electric vehicles (EV). Three back-up signals used for the evaluation were categorized into three types: broadband, tonal and multi-tone. The reversing sound for a Nissan Leaf (EV-first mass production) will also be included as a benchmark for the other three sound signals. The sample sound was generated based on the human hearing threshold in several individual related areas; age-related, normal and working noise exposure frequency range. Each sound was evaluated in turn by the respondents in a nearby neighborhood, college, town area and rural area in terms of level of annoyance and its suitability as an EV back-up sound to alert pedestrians as they run quietly on the road, which can cause a hazard. Every tested sound perception result is based on the place where the respondents live. An appropriate sound for a quiet vehicle can help pedestrians to detect it and at the same time maintain acceptable environmental sound levels.

Windscreen wiper vibration problem is now becoming one of the comforts and safety concerns because it can be annoying to the driver and passengers and also affect concentration of the driver while driving. This paper investigate the problems by measuring the wiper blade contact force and vibration level on laboratory wiper experimental rig and wiper system on two different sedan passenger cars operated similarly. In order to measure the vibration and contact force along the wiper blade, MMA7660 accelerometer and a thin film force sensor FSR was used. The contact force is measured at four points; Points 1 (inner tip), 2 (middle blade) and 3 (middle blade) and Point 4 (outer tip), along the wiper blade. Based on the measurement, it was found that the contact force is much higher at Points 1, Point 2 and Point 3 compared to Point 4. For vibration level, higher vibration is occurred at Points 2 and Point 3. It can be conclude that the bigger the contact force value act on windscreen the bigger for the vibration level to be produce. From this founding, further research can be conducted and tackle the problem at certain point along the wiper blade.

This paper describes and discusses the development of the control system to produce engine sound as audible information for pedestrian to detect the Electric Vehicle (EV) presence instead of alarm type noise. EV produces less noise when travels at low speed condition and can bring unexpected accident to the road user. Various alarms were introduced by the car manufacturers to prevent this problem but the implementation of this system has brought some inconveniences to the EV user since EV is known for its calm and quiet. The engine sound that will be the output of the control system must meet the International Standard Organization (ISO) standard as minimum noise emitted from the vehicle and also as cue sound for pedestrian detection. The introduction of engine sound in EV at the low speed manoeuver is expected to resolve the safety issues among pedestrian and at the same time maintain the EV quality to its user.

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