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Friday, July 26, 2013

Preparing For A Track Day Part 1: Data Logging

Introduction

I've been into Formula 1 since about the 2004 season and I've always thought it would be a ton of fun to drive a car around a racetrack. I got the chance to have a very small taste of something like that in 2010 when Clarkson University's alumni association hosted a "drive and dine" at Watkins Glen International. Basically, it involved paying a small fee to drive three paced laps of the track and then have a buffet dinner at the Glen Club building at turn 1. It was a nice time and even though the laps were paced it was really easy to give yourself a gap and push through a couple of turns before coming up to traffic so I had a lot of fun. Also, it really made me want to do it for real.

A couple of years later I remember reading articles online previewing a new sports car that was being developed jointly by Subaru and Toyota. Everyone seemed excited because the car was light, rear wheel drive, and very inexpensive by sports car standards. It was launched as a 2013 model in the US called the Subaru BRZ / Scion FR-S (it's called the Toyota GT86 in the rest of the world) and it seems like every reviewer loved it. Lots of reviews also said the car felt right at home on a track.

Jezza looks so happy!

At the beginning of this year I decided to get a little more serious about living out my fantasy to be a race car driver and with permission from my wife (thanks babe!) I bought a BRZ in April and signed up for a two-day driving school at Watkins Glen with Trackmasters at the end of August.

Prior to my track days there are a couple of things I want to do to prepare the car and the point of this post is to talk about the first thing I decided to address - data logging.

Goals

One of my biggest concerns going into a track day is the stock cooling system's ability to cope with the heat that'll be generated with track use. I haven't seen hard data one way or the other, but I don't want to take for granted that everything will be fine. My primary goal is to have a way to see how the car is doing in as close to real-time as possible by monitoring a couple of important numbers like oil and coolant temperature. My secondary goal is to be able to conveniently review and share any data I generate after my track sessions are over.

Solution


My needs are fairly simple - unlike some of the fancy and expensive systems used in purpose built race cars I don't need to monitor a lot of different parameters at once and I don't need great resolution. I can live with a longer resolution (a second or two would be fine) and every piece of data I'd like to see is already being monitored by the car. I figure the best way to achieve my primary goal, then, is to take the data I'm looking for from the OBD-II bus and stream it to a mobile device for viewing and logging. Actually doing this requires two things -

First, I need to get the data that the car is monitoring and broadcast it wirelessly. To do that I'm using an ELM327 V1.5 OBD-II to Bluetooth adapter. You can find them on Amazon.com or Ebay for around $15.

An ELM327 OBD-II to Bluetooth adapter

Second, I need a way to capture the data that's being broadcast and interpret it. I'm doing this with and Android smartphone and there are actually quite a few apps out there that can do the interpretation. I'm choosing to go with Torque Pro.

Setup

Installing the OBD-II to Bluetooth adapter is very easy - it just needs to be plugged into the car's OBD-II port and paired with the receiving device.

The adapter plugged in to the OBD-II port under the dash near the center console on the driver's side

Setting up Torque Pro is also quite easy. To begin, a profile is created for the car you'll be using the app with. Then, by navigating to 'Settings' under the main menu the program settings can be accessed and there's option there labeled 'Data Logging & Upload'. From there, selecting the top option labeled 'Select what to log' brings you to a screen where you can add OBD-II PIDs (parameter IDs) to log in addition to a few defaults that are always there.

The list of PIDs that will be logged

I'm choosing to log speed, engine RPM, ambient air temperature, intake air temperature, coolant temperature, and oil temperature. All of these PIDs (except oil temperature - more on that in a second) are automatically detected and available by default.

Logging Oil Temperature Through OBD-II

A special note about accessing oil temperature data via OBD-II - you can do it on some cars, but many cars either don't support it or only support it using a non-standard PID. Fortunately, the BRZ and FR-S support it using a non-standard PID and Torque Pro allows you to specify custom PIDs to monitor.

FT86Club.com user andreyiv figured out the settings needed to monitor the oil temp PID and his instructions made his way to a sticky'd thread here - http://www.ft86club.com/forums/showthread.php?t=23530. I'm able to use his settings and it they work perfectly - thanks andreyiv!

Creating a custom PID for oil temperature

Oil temp is probably the most important piece of data that I want to see so I'm very glad to find that this works.

Usage

To start data logging I access the Realtime Information screen in Torque Pro and select 'Start Logging' from the main menu:

Click 'Start Logging' to begin

After I'm done driving I can access the same menu and select Stop Logging to end my data log. The log files are saved in .csv format in a folder called 'torqueLogs' on my phone's SD card. Here's an example of a data log that captures a drive I took this morning - https://docs.google.com/file/d/0B-b50HEZXbX5REswN1gxak9JR3M/edit?usp=sharing

Up to now I've only talked about using Torque Pro to log data for review after I finish driving. I should mention that you can also set up a customizable, real-time, virtual dashboard of whatever parameters you'd like to see independently of what's being logged. I don't know if that feature will be valuable to me on track (I don't think I'll be allowed to mount my phone in a visible spot and I probably shouldn't be paying attention to it anyway) but it's definitely cool during normal driving.

Screenshot of my custom dash on Torque Pro taken while stationary, just after starting the car

Conclusion

The combination of an ELM327 OBD-II to Bluetooth adapter and Torque Pro definitely satisfy my primary goal of being able to monitor how my car is doing in real-time. It's also a very affordable solution - I paid under $25 for both the adapter and the app.

The only thing I'd like to make a little easier is going through the data logs. I can use an app that lets me view .csv files to go through my logs but that's cumbersome and not very pleasant on a smartphone. If I'm in front of a computer I can transfer the files and use a program like Excel to go through my data conveniently but that's not realistic at the track. What I'm looking for, then, is a way to upload my data logs somewhere and have them made available to me graphically. Also, I'd love for that to happen over the Internet without the need for any client software. Anyone that's used fitness sites like Strava, MapMyRide, or RunKeeper will know exactly what I mean. I have a couple of ideas for accomplishing that - check back soon for a follow up post.

Also, please check back soon for a Preparing For A Track Day Part 2 post where I'll address another aspect of the BRZ that I'd like to improve - the brakes.

Data logging is all set up!

08/26/2013 - Update - Preparing For A Track Day Part 2: Brakes has been published

Tuesday, July 23, 2013

Introduction

I've always thought it would be a good idea to set up some kind of information repository for myself on the Internet. It seems like every time I work on something I spend a bunch of time doing research online, and at the conclusion of every project I tell myself that I hope I can remember the useful things I learned later if I need them again.

I've also been wanting to register a domain name for myself and establish a web presence.

This Blogger site is kind of like the merging of those initiatives. My vision for this blog is to be a place where I can do two things - store information that I'll want to reference later (probably in the form of how-to guides and work logs) and write about things of interest to me.

I'm also very hopeful that I'll be able to help (or at least provide reading material for) others with similar projects or interests. I know I've done more than my fair share of forum lurking and Internet browsing without any return contribution until now.