Programming for IoT - ICT4SS @politecnicoditorino - 2020/2021 Developed by Jacopo Braccio, Francesco Conforte, Sara De Luca, Matteo Mastrota.
Car2Smart is an IoT microservice oriented platform which aims at improving car sharing services, with a particular eye on safety. One of the major reason of car accidents is alcohol. Preventing a person from driving in an alterated state is crucial for road safety and could eventually save lives. With Car2Smart, before car's rent starts, the user must take an alcohol test in order to be able to unlock the car. If the alcohol test is negative, the booking can start, otherwise the user is not allowed to drive and will be prompted to find an alternative. Furthermore, Car2Smart offers a fast way of noticing accidents and vandalism against car fleet and a control system for air conditioning in order to reduce wastes.
The general platform architecture is reported in the following image:
The following components can be distinguished:
- Arduino: used to take the alcohol test;
- Raspberry: emulates the car control unit;
- Telegram: allows fast communication both with the users and the car sharing company;
- Dashboard: used for decision making by the car sharing company;
- MQTT broker: responsible for receiving all MQTT messages, filtering the messages, determining who is subscribed to each message, and sending the message to these subscribed clients. HiveMQ was the choice.
For each components, one or more microservices are implemented. Each microservice is dockerized to deploy and replicate the system more quickly and easily.
The catalog is the core entity of the platform. It contains information about alcohol thresholds, air conditioning settings, car fleet (sensors and status of the car) as well as information on how to connect to the MQTT broker and to the telegram bot. The catalog is exposed using HTTP REST apis, following a RESTful paradigm. It is reached by the other microservices to get the information needed.
Running on Arduino. This service is used by the user to take the alcohol test before unlocking the car. A MQ-5 Gas sensor is calibrated on the alcohol curve available on the data-sheet, by using power regression. Thanks to it, the breath alcohol level is collected and its value is published on the MQTT broker by using the topic smart2safe/arduino/<car_plate>/alcohol_test in the SenML format.
MQ-5 gas sensor
Running on Raspberry. It checks on the catalog the topic on which Arduino is publishing, subscribes to it to catch messages containing alcohol values and checks the thresholds in order to unlock the car or not. If the alcohol test is positive, it communicates with the Telegram bot via HTTP, where it posts a message containing information for the user such as: measured alcohol level, foreseen fine, car impounding, license suspension and foreseen months of prisons according to the Italian Law.
Furthermore, it publishes on MQTT broker a message useful to generate statistics on the dashboard by using the topic smart2safe/raspberry/<car_plate>/alcohol_test.
Running on Raspberry. Through the use of a DHT11 sensor, the temperature and the humidity inside the car are collected and published on the MQTT broker in SenML format at the topic smart2safe/raspberry/<car_plate>/aircondition. According to the collected values and thresholds defined in the catalog, the air conditioning may be turned off.
DHT11 temperature and humidity sensor
Running on Raspberry. By using a microphone, it listens to the surrounding and performs audio processing to detect if a glass breaks. In case of break, it sends a HTTP post message to the telegram channel that will eventually notify the car sharing company and publish the event on the MQTT broker at the topic smart2safe/raspberry/<car_plate>/window_monitor.
It subscribes to topics smart2safe/raspberry/# to retrieve messages containing values to be visualized in a nicer way thanks to the InfluxDB Cloud dashboard tool.
Dashboard view preview
Telegram represents the user awareness side of the platform. A bot reachable at @Car2Safe is created. The bot can perform two main tasks:
- Publish on the 'Car2Safe - Damages Updates' channel whenever it receives a HTTP post request from the 'Window Monitor' service. The message will contain information about the received damage.
- Contact the user in case of positive alcohol test and prompt him to call its emergency number of the taxi company instead.
Telegram Channel - Telegram Bot
Here is a quick video on how the platform actually works:
