Le nostre tesi
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Politecnico di Torino

Computer Engineering

Master's degree

Autore

Giulio De Giorgi

2021

Design and prototyping of an Advanced Acoustic Vehicle Alerting System for Electric Vehicles

logo politecnico di torino test

Politecnico di Torino

Computer Engineering

Master's degree

Autore

Giulio De Giorgi

CAN-BusPython
Relatori Teoresi coinvolti

Massimiliano Curti


Abstract

In the past decade, Electric Vehicles (EV) surely became a trending topic in the automotive world. Most car makers developed this new technology, some of them electrifying models they already produced, such as FIAT with its 500e and Ford with its Mustang MACH-e, some of them adding a supporting electric motor to the Internal Combustion Engine (ICE), such as Toyota with its Auris and Jeep with its Renegade, and some others again making brand new models, completely electrified from the beginning, like Tesla with its Model S and Model 3.

This transition is quickly leading to one of the biggest changes in automotive history and, as a result of the exciting interest in electric mobility, brings to the attention of car manufacturers a lot of new challenges. One of these new challenges is to make electric (or hybrid) vehicles emit sounds: this particular problem is crucial, in fact often the sound of electric motors is quite inaudible, both from the cockpit and from the outside.

While external sound production is being subject to regulation from the main regulator authorities – US Congress, the Japanese government and European Commission are the main promoters of the regulation -, internal cabin sound is not subject to any rule. For this reason, internal sound can be designed not only with the alerting aim in mind but also with the proposal of giving back the driving feeling to the driver, lost with the transition from the Internal Combustion Engine to the Electric Motor. In addition, internal sound generation can be treated as a branding characteristic and car makers can develop original sound propriety in order to become more recognizable to the buyers.

With the paramount help and the contribution of Teoresi S.p.A., a leader company in the consulting world, which core area of expertise is the Automotive world, this project has come to the light and led to the prototyping of a working device that is able to make an Electric Vehicle emit actual sound.

In this Master Thesis, different design approaches for internal cockpit sound generation will be explored. A sound generation server will be employed in both approaches, using “supercollider” as programming language.

The communication between the vehicle’s Electronic Control Unit (ECU) and the sound generation server will be managed via a python script, that will receive and filter vehicle CAN bus messages and will send the commands to the sound generation server, using “Open Sound Control” socket (OSC).

All these technologies are open source tools and already widely employed in the automotive world. In the end, a desktop GUI application for test benching the sound generation algorithm without using the real vehicle will be developed, using “python” and “kivy”.

Objectives

Design of an advanced system for sounds playing on electrified vehicles (AVAS). The sounds will be designed to be played inside the vehicle. The goal is to evaluate which is the most efficient and effective way to give back the driver the sensations of being at the wheel.

Research methodology

Sound design via SuperCollider and granular synthesis.

Conclusions

The approach of sound generation through granular synthesis is particularly suitable for the design of sounds through the combination of different pieces. The sounds, suitably synthesized, can then be modulated on the basis of external parameters to provide signals to users.

Future developments

Porting analysis of the activity on an embedded board with less resources and lower costs. System application analysis to sectors other than Automotive (eg railway, industrial, ..)