Hi Arduino Forum, this is a series of questions regarding an automotive project I wish to engage.
I'm thinking about a "drive by wire" project and my first concern is the stability of the Arduino system.
Here are some questions i got towards a Arduino board:
is it strictly meant to be used as a (relative) static device
does it crash (during vibrations for instance)
can programming get corrupted
can the program survive without power and if, how long can it manage to do so
How much time does it take to start a programmed (and hooked up) Arduino
What is the advised temperature range for an Aduino device.
Any other information concerning the "automotivety" of Arduino is welcome.
Thanks in advance
The data sheet says that the processor chip should not be used in medical or automotive applications. However that is a please don't sue us line.
There have been many automotive arduino projects.
Mind you a car is a hostile environment electrically and you need to take precautions with any electronics and the arduino is no exception. It needs good decoupling and possibly suppression of noise generatoring components in the car.
Hi,
I use commerial and home made Arduinos in RC Cars at high speeds and remotley. An RC Car is subject to electrical noise (maybe not the same degree as an ignition spark) and significant mechanical vibration, so far I cannot recall any problems not caused by my code - and that right there is the key, I do an awful lot of testing on the bench and on the road and you will need to aswell if the Arduino is going to play any part in the cars velocity or direction or the control of expensive equipment which could destroy itself, 10 times of of 10, the problem turns out to be me.
An RC car will not be even close as electrical hostile as a real car. Also an RC is less likely to kill people if its controls fail. Hence you have a second try. With a real car you or someone else could be killed.
With other words: a "drive by wire" project for a real car is no means a beginner project.
The "Do not use for Medical or Automotive use" is a fairly standard boilerplate. Basically what it means is that without special clearence with their legal department they will assume nothing for any of their components used in those applications. Means they want to sign a contract that makes you responsible for anything that happens, not them. For one off items, they would use such warnings to say that they didn't approve of their device being used in an application and therefore they will assume no responsibility for the suitability for that application. In other words - you're on your own.
A better question is how are you going to use the Arduino, and have you designed for the physical environment that it will be exposed to. And are you going to build in suitable failsafes so it the computer (whatever computer) fails the vehicle will not become a hazard to others.
As far as your questions - Can it Crash - YES, though that is a function of the quality of programming, and not an inherent problem with the device. Vibration - not a problem with the chip, but might be with how the board is constructed, if the vibration is bad enough to break electrical connections, then things will fail. Is your design adaquate to the physical demands? Can programming get corrupted? - It is possible, but highly unlikely as long as the environmental and electrical specs are followed. More likely to be caused by faulty programming techniques. Can the program survive without power? Yes, we use that feature all the time. How Long? depends on the cosmic rays and the environment.How long does it take to start? The Arduino starts executing code in milliseconds, how long will your code finish initializing? don't know, how cleanly do you code? How complex is your initialization? Might another processor be better for your application? Don't know. If you have no experience either will be equally bad, if you have experience with another processor it might be a better choice as you have already learned ho to use it. Maybe another processor would be better because it has more memory options.
Until you define the project and its needs, you will not be able to make a good choice of what processor to use.