Arduino Telematics Kits are designed to putting up a data logging and monitoring device with OBD-II, GPS and motion sensor data access.  This users guide contains information to get start with the kit and the Arduino sketch designed and provided for them.

3 different kits are provided at different size and functionality, they are:

  • Kit #1 – Arduino Nano based with OBD-II, SD card data storage and monochrome OLED display
  • Kit #2 – Arduino MEGA (compact) based with OBD-II, GPS, motion sensor, microSD card data storage, BT 2.1/BLE data streaming, 2.8″ color TFT LCD display
  • Kit #3 – Arduino MEGA 2560/ADK based with OBD-II, GPS, motion sensor, microSD card data storage, BT 2.1/BLE data streaming, 3.2″ color TFT LCD display

NanoTimer

NanoTimer is a sketch developed for Arduino Telematics Kits #1. The sketch implements feature of a PerformanceBox. It measures time used for a car to accelerate from 0-60km/h, 0-100km/h, 0-200km/h and time for a 400m dash.

The sketch references following custom Arduino libraries:

NanoLogger

NanoLogger is a sketch developed for Arduino Telematics Kits #1. The sketch features OBD-II data access, data logging and live data display.

The sketch references following custom Arduino libraries:

MegaLogger

MegaLogger is a sketch developed for Arduino Telematics Kits #2 and #3. The sketch features OBD-II, GPS and motion sensor data access, data logging, data streaming and live data display.

The sketch references following custom Arduino libraries:

Configuration

MegaLogger has several configurable options all stay in the config.h file. Major options include:

  • OBD_MODEL – defines the model of OBD-II Adapter (UART or I2C)
  • USE_GPS – defines whether GPS is used
  • USE_MPU6050 – defines whether MPU6050 (accelerometer & gyro) is used
  • ENABLE_DATA_LOG – toggles data logging on microSD card
  • ENABLE_DATA_OUT – toggles data streaming (to mobile devices via Bluetooth)
  • STREAM_FORMAT – sets streaming data format (binary or text)

OBD-II

The kit connects to the OBD-II port of a motor vehicle via OBD-II Adapter for Arduino. There are two versions of OBD-II Adapter available, UART and I2C. The UART version provides ELM327 command-set via serial UART at baudrate of 38400bps. The I2C version works as an I2C device which is accessed by I2C address for OBD-II data access. It also integrates I2C MEMS sensor which provides accelerometer and gyro. OBD_MODEL define in config.h should be corresponding to the model of the adapter. The OBD-II Adapter should be connected at Serial1 or I2C interface and is access from Arduino by OBD-II library.

GPS

The kit comes with optional GPS receiver which should be connected at Serial2. The incoming NMEA data stream is parsed by TinyGPS library.

Motion Sensor

Motion sensor (accelerometer & gyro) are embedded in I2C version of OBD-II Adapter. They are accessed via I2C by MPU6050 library.

Data Logging

The kit provides complete data logging for OBD-II, GPS and motion sensor data. The data is stored on microSD card if present. Standard Arduino SD library used for accessing microSD card.

The data is logged in a simple CSV text format.Each line represents a record with time, data type and data value like this:

[Time Elapsed],[Data Type],[Data Value 1],[Data Value 2],[Data Value 3]

Time Elapsed is the time elapsed in milliseconds since previous data record. Data Type is the OBD-II PID which is defined in the OBD-II library (e.g. 0x10C is engine RPM). Here is an example data clip:

169,10D,0
171,111,12
170,143,21
165,10B,30
175,10C,705
169,10D,0
170,111,12
…

GPS data is defined as special PID which OBD-II standard does not use and are defined in datalogger.h file.

#define PID_GPS_LATITUDE 0xA
#define PID_GPS_LONGITUDE 0xB
#define PID_GPS_ALTITUDE 0xC
#define PID_GPS_SPEED 0xD
#define PID_GPS_HEADING 0xE
#define PID_GPS_SAT_COUNT 0xF
#define PID_GPS_TIME 0x10
#define PID_GPS_DATE 0x11

Motion sensor data is defined as following.

#define PID_ACC 0x20
#define PID_GYRO 0x21

They will have 3 data values for all 3-axis (X/Y/Z)

Data Streaming

Live data can be streamed to a mobile device via Bluetooth (BLE or 2.1) module which is optionally connected at Serial3. Two stream data formats are available, text or binary based. Text based format is same as data logging format in form of CSV. The binary format is based on a framed data format and is used by streaming data to iOS device with Freematics OBD App installed.

Data Display

Kit #1 comes with a 1.3″ OLED module based on SH1106 controller. Kit #2 comes with a 2.8″ color TFT LCD display based on ILI9325D controller. Kit #3 comes with a 3.2″ color TFT LCD display based on SSD1289 controller. The live data will be displayed on the screen. The LCD display is driven by MultiLCD library.

For Kit #2, the definition of following should enabled in config.h.

LCD_ILI9325D lcd;

For Kit #3, the definition of following should enabled in config.h.

LCD_SSD1289 lcd;

Source Code Repository

The source for all the sketches and libraries are hosted on this Github repository. To download the latest source code as a zip file, click here.