OBD-2 based Vehicle Data logger

Designing a platform to help consumers analyze and track their vehicle stats and driving dynamics.

  • Product Research
  • Design
  • Design
  • Development
The obd web application showing a selected user annotation.

What is OBD-II ?

OBD-II is an enhanced diagnostic monitor, built right into the vehicle. It's designed to alert the driver when emission levels are greater than 1.5 times the emission levels for the car as it was originally certified by the EPA (Environmental Protection Agency).

OBD stands for On Board Diagnostics and the II added to the OBD (On Board Diagnostics) name represents that it is the second generation, the successor to the OBD I system used on EPA-certified cars starting in 1988. Unlike OBD-I, OBD-II is designed to detect electrical, chemical and mechanical failures in the vehicle emission control system that might affect the vehicle emission levels.

The OBD-II protocol is rather simple in theory, but in practice manufacturer-specific additions and omissions from the official specification make communication more difficult. To communicate with the ECU, OBD-II Parameter IDs (PIDs) are sent, and the ECU responds with anywhere from one to twenty bytes. PIDs are grouped into modes which range from Mode 01 to Mode 09. The mode my project is particularly concerned with is Mode 01, because that mode provides real-time data. Other modes, such as Mode 03, provide Diagnostic Trouble Codes (DTCs) and general information like the Vehicle Identification Number.

Our solution was to allow users to be invited to a layer, where they can see others’ annotations and make their own.

The layers sidebar design, now with user profiles.
Multiple user annotations on a shared layer.

Objectives

OBD-II Port is used for On Board Diagnostics of the vehicle. This helps to alert the driver about the emission control of the vehicle. This port can as well be used to check various other parameters such as vehicle speed, engine rpm, engine run time, throttle position, engine coolant temperature, engine coolant level, trouble codes, fuel type etc. This can help to monitor the mileage and fuel consumption of a common user and can also be used to monitor the driving habits of a driver as to identify whether he is over-speeding.

This feature is very much useful for parents to keep a track of their children's driving habits.

The RAW data is decoded in order to obtain the actual values of the selected parameters for the vehicle. The Android OBD-II Reader Android Application is used to display the values logged in real time for the system.

Objectives:

1) Write a Python program that runs on the Raspberry Pi to establish connection with Bluetooth OBD-II scanner and record various parameters to SD-card.

2) Write a Python program that exposes the collected data through an API and displays it on the GUI of the Raspberry Pi.

3) Using Android SDK, develop an android application capable of data logging through the Bluetooth OBD-II scanner.

The new My Slides tab in obd, showing annotated and favorited slides.
An annotation preview popover with statistics for shape perimeter and area.

Meaningful details

OBD-II analytics can be very helpful in monitoring driving habits. Consider a device that allows parents to monitor their children's driving to teach them about safety and proper driving techniques. This kind of device would reduce accident rates and create better drivers.

Progressive Insurance has a device called Snapshot which analyses driving habits and rewards good driving with up to a 30% discount. This device plugs into the OBD-II port and uses the real-time PIDs to read data, much like this project.

Analystics on the OBD sensors reporting fuel level over OBD-II would probably benefit consumers the most because it would allow one to identify what kinds of driving habits minimize fuel consumption. Not only would it save a few Dollars at the gas station, it would also help to reduce global pollution.