Plug-and-Play for Automobile Embedded Systems

wskellenger writes "This article in the EE Times describes Autosar, a consortium of German automakers and suppliers that aims to standardize vehicle software infrastructure. In this way, vehicle software can be used in different ECUs, reducing complexity and development time for OEMs and suppliers."

Comments

The future of car automation

[Matey-O]

Things have been going in this direction for quite awhile. The Corvette in 97 went to a serial communications protocol, talking to 14 different control units. It also had a throttle by wire system that eliminated a LOT of complexity in the traction control, cruse control and throttle applications. Active handling, a SIGNIFICANT feature, required a software change and two sensors.

The next step is to get sensors to talk this protocol. Rather than having a dumb sensor that goes to a control unit that interprets the message, you have a temp. sensor that the manufacturer doesn't have to worry about. They just need to look for a temperature unit reporting water temp, or another unit reporting vehicle speed on the wire.

Then the cruise control, the radio, the speedometer, etc all just have to listen for that packet that says 'wheel speed is 60 mph'.

the Cool thing is, the vendor that makes the Vehicle Speed Sensor might do it today for $50. Next year it may be $42, the year after, they might redesign it to have zero moving parts (optical) and with custom asics, make it a $12 part. Will that translate to a cheaper vehicle for you? probably not...but it'll make your car last longer, and will be easier to troubleshoot.

The BMW/MINI Cooper saga.

[sbaker]

The new BMW MINI Cooper has an ECU built by Siemens and programmed by yet a third company. BMW claim that they don't even have a copy of the source code for their own car! The same ECU is used in a variety of engines. So in order to have the code optimised for a particular car, the software "learns" - over several tankfuls of gas - how best to drive the car. Since cars change over time, it continually re-learns. If you add a new air-filter for example - the effects of doing it only gradually appear - over about three tankfuls - as the ECU learns to adjust the fuel/air mixture again.

This has consequences. Firstly, when you buy a new MINI Cooper, you get really poor gas milage for the first few tanks of gas - but gradually (as the ECU learns), it gets better.

So far, so good.

But the MINI has a problem (known as the 'stumble' amongst owners) - it's a software bug that appeared in 2003 model-year cars - older cars don't have it unless they upgrade to the 3.3.x version of the ECU software for some reason.

Under the special combinations of high air temperatures (and perhaps only in low humidity) in the summer in the southern USA - and with 'Reformulated Gasoline' that we get here in Texas and in Florida - the car sometimes stalls out at dangerous times. (eg You pull out into traffic - and the car stalls halfway across the road).

The stumble was VERY hard to diagnose - both because BMW couldn't reproduce the problem - it took a lot of MINI enthusiasts across the US to finally figure it out.

We (within the owner's community) decided that this couldn't possibly be temperature related - because the car would still stumble in the cool of early morning. We decided it couldn't be reformulated gas because we could drive to Oklahoma - buy a tankful of "the good stuff" - and still experience the stumble.
During a heatwave in Washington (who also have reformulated gas) - there were no reports of 'stumbles'.

These were cases where diagnosis was made almost impossible because the ECU had *learned* to stumble - and needed either cool temps or better gas for THREE TANKFULS in order to recover from it. People who experienced a short heatwave - or who bought only one or two tankfuls of reformulated gas didn't see the problem.

In consequence, it's taken over a year to convince BMW that there really is a problem and to find out what it is. However, BMW themselves can't fix it. They have to work through Siemens to get to the third company who programed the ECU so it could be fixed - and those guys didn't want to just fix it "the easy way" because it would have the potential to screw up performance in other kinds of car that use the same ECU software.

We are promised a fix for the stumbles - sometime in December.

This is all VERY yukky and unsatisfactory.

The thought of trying to write OpenSource ECU software came to mind - and there are some projects out there to do just that. This ECU has reloadable software - using a serial port connection that appears just under the steering wheel (used for emissions control stuff too). You can buy a cable to adapt the car's serial port to that of your laptop or PDA - and there is even software to let you read out and reset the engine management error codes in the comfort of your own driveway.

Armed with a laptop, your car dealership can upload new software into your car in about 20 minutes.

However, attempts to do this ourselves resulted in a fascinating inside into what the world of Palladium/DRM. When you tell the MINI "Please accept a new software load" - it sends you back a 16 bit random number. You are supposed to execute some predefined math operations on that number and send back the result as another 16 bit number. If you get the answer wrong, the car completely shuts down for 3 HOURS! You can't even start it under those circumstances - let alone try again with the software download. Obviously, the math operations you have to evaluate to solve this challenge/response scheme are secret.

So - welcome to the world of the future. For some of us it's already here!