SparkFun Forums

[Troikacarleton]

Hi
I am building a full side and front airbag protection system into my 1989 Jaguar XJS V12 convertible.

The airbags are fitted and deployment tested. The activation wiring is in place back to the ACU.

iOS all based on a 2010 Ford Mondeo 4 system. However ford will not help with circuit tracing or testing because they don’t want any responsibility.

I am a research physicist reasonably expert in analogue control circuitry, research needs analogue in practical design before submitting the design for solid state digital unit build.

I want to use Sparkfun accelerometers for the side and front impact sensors with similar in a bespoke ACU as safing sensors.

My question is this:
Do 2/3/5/10 g SparkFun accelerometers activate only in a straight line or can they activate at an angle say 30 deg.

I appreciate that a 3G accelerometer will activate if set at an angle of 30 deg with a straight line impact of 4g.
Similarly a 2 g accelerometer will activate at 2.7g is set at 30deg to the impact direction.
However if the accelerometer activates at its design spec (3g accelerometer activates at 3g straight line impact as well as 30deg impact) across 30deg either side of straight line then I don’t need to combine accelerometers to get the impact angle flexibility.

I also need to build a self test means into my bespoke ACU to conform with UK law on airbags.

Hope you can help
Dr James R Bell

[TS-Chris]

Hi James, and thanks for your post.

All the accelerometers we carry are 3 axis types and will register acceleration no matter what orientation they are in. You would just need to read acceleration on 2 (or three) axes and sum the output on the axes of interest.

That being said, we need to let you know that our products are not intended to be used in a life safety application and we don't recommend using them where a failure or malfunction could result in danger to life or property. They would be fine to prototype with, but you really shouldn't be using these parts in a final product as they are only hobbyist grade.

From our Terms of Service:
SparkFun does not approve or recommend the use of our products or resources in critical life-support or medical devices, or for any use or application in which the failure of a single component could create a situation in which property damage, personal injury or death is likely to occur. Don't hack your pacemaker! And if you do, you absolve SparkFun and/or the manufacturer of the product in question of all damages, costs, and expenses that may be incurred, including without limitation, attorney fees and costs related to any lawsuit or threatened lawsuit arising out of the use of our products in unauthorized applications.

We wish you luck with your project, but please be careful! We wouldn't want to hear about someone getting hurt if a sensor failed.