Transmits real-time automotive sensor information to a client smartphone or tablet running an ODBII monitoring app.
The most common application is to provide real-time sensor information for classic vehicles that either do not have an ECU or a sensor bus with an OBDII connector.
The common setup will be a set of automotive sensors connected to the Arduino microcontroller (MCU) running as the simulator. Equipped with a Bluetooth module, sensor information will be sent to a client when requested. The client will generally be a smartphone running an OBDII app, such as Torque.
This program implements the aqcuisition and calculation of sensor values, and transmission of those to the client using OBDII PID structures over the ELM327 protocol upon request.
+-----+---+ +--------+ Xx +----+
| | | | +--+ | Xx XX |----|
| +++ | | -+ +- | Xx XX XX || ||
| -> | | +---> | -+ +- | XX X X || ||
| +++ | | +--+ | Xx XX XX || ||
| | | | | Xx XX |----|
+-----+---+ +--------+ Xx +----+
Sensor MCU + Bluetooth Smartphone
(OBDII scan tool or tablet
simulator)
Other than the microcontroller, the only basic requirement is the addition of a Bluetooth serial communication module. The HC-05 module, which generally comes mounted on a ZS-040 breakout board, is a good choice for instance.
This software was tested with an Arduino Nano and an HC-05 Bluetooth module as shown:
To interface each sensor to the microcontroller additional signal conditioning circuitry is also required, which needs to be adapted to each particular sensor's characteristics.