Backyard Aquaponics
A place to discuss aquaponics

I know, I know

Pffft fun stuff first!

Will keep an eye open for your new thread

I know right

The ADXL-05 is a breeze (though now obsolete I am sure there is a virtually identical replacement), 3 resistors, 3 caps and 1V/g output.
I have an ADXL-202 dual axis dev board with 0v-5v output, I'll play with that first.

I have a few accelerometers laying around. I was planning on trying to make my own 9DOF sensor for a model heli, but work got hectic and i had to put my electronics up. My interest is coming back with a vengence! Plus i found out that parallax is finally support a C/C++ compiler for the Prop/PropII, so as im learning C i might be able to make sense of your code.

My initial interest for accelerometers was in inertial data logging in race cars.
I went on to make a swash plate leveller for model helis to aid flight training.
Was intended to be commercial, but at the time my personal life fell apart and I lost interest.
Really fun project watching the heli fly itself in the garden, it hovered perfectly, hands off the controller.

Needless to say, if you need any help with the highly idiosyncratic aspects of C, PM me, or start a thread, always willing to help.

My first encounter of accelerometer was in making an inclination datalogger while i was at tafe. It never really worked at any degree of accuracy (noise was a huge problem) but i learnt a huge amount.

I never really expected to get my 9DOF sensor working. Maths and electronics really are not my strong points. It is something i am still keen to try, but seems to get lower and lower on my priority list as learn about new things. Like AP for example has a higher priority with some sort of datalogger. I would be keen to see a vid of your heli hovering if you have one?

Thanks for the offer for the help with C. You may well come to regret it though

Also for level sensing, this may be a bit easier.

http://www.youtube.com/watch?v=0JL85O1BM8g

I am sure the probe can be made to be a bit more elegant. I have seen better versions, but this was the best with a 2 second search.

Also this might be intersting to you aswell.

http://www.parallax.com/Portals/0/Downloads/docs/cols/nv/vol1/col/nv27.pdf

The only thing would be how well it would handle any slime build up.

Nice idea, but I wouldn't be happy with metal in an AP system.
And as you rightly say, how capacitive is slime

So I'm the bad guy now huh ?

I like this one


Pretty easy to do with a resistor and temp sensor. Plus side is you only need one sensor for temp and leve. Neg side is that you have to pick a fixed height for the sensor, which isn't so bad i guess.

That one occurred to me when I made the temp sensors.
Only good for water low though.
I will use it to verify the main level sensor.
Turning the pump off is obviously critical to the fish, so that decision should be made with (at least) two completely separate sensors.
Imagine coming home from work to a tank full of dead fish 'cos a wire fell off the main sensor.
In the sump, I plan on having four sensors, possibly five.
Tilt which gives the level (accelerometer)
Resistive low and critical.
Temp probe will be in there anyway and would sit somewhere between the Low and Critical resistive sensors.
The fifth would be sump full, but that's not really critical, so the accelerometer alone would be enough for that.

sounds good, how goes the new GBs ?

One finished and rolled into place, the label on the sealer says wait 7-14 days for it to cure, pffft 24 hours is long enough for anything to dry !
Another half finished, been bloody hot today, had to move some of the shadecloth over me, bugger the plants for a day!
Not one line of code written today, so a constructive day.
Off to the pub now methinks.

I dont get this.

Is this saying use a resister to heat the temperature probe so you get around the possibility of the air temp and water temp being the same and giving a false reading?

BW, yeah mate. If you are heating the temp sensor in air you can expect a certain temperature rise. If you heat it in water (provided its not insulated much) the temp rise will be much slower, because the water is cooling it down much faster than the air will.