Hi!
First I'd like to say hi and that I am very glad I finally got onboard here! I got lots of future projects in mind and
I am very exited about getting to know this tech. I am not new to diy communities but haven't played around with arduino at all.
I have a specific project in mind and wanted to see if you geniuses could point me in the right direction , if at all possible.
I have an instrument/ sensor that measures moisture on the surface of a, well, surface. For example a wall.
If I measure over this wall I would have to take notes every decimeter to get a picture of the walls moist level. Where it's most and where it's less. If I do this very thoroughly I can later get a nice 2d graph with coloring that shows me a picture of the moist level. A lot of work though!
Is it possible to do this with arduino?
I am thinking tracking movement with accelerometer and continuos reading moist values from sensor.
What do you guys think? Is this possible? I am totally newbie so please be gentle!
Am I totally off here?
Thanks for your time reading. Hope I managed to explain myself somewhat clearly! Would really appriciate any kind of feedback!
How big is the sensor? Does it need to always be a specific distance from the wall, in constant contact with the wall? Maybe describe the physical process of taking your readings.
How fast can you move the sensor? How accurate do you want the position to be. Accelerometers (obviously) measure acceleration so if your unit is moving at constant speed there is no acceleration. To get distance from acceleration requires double integration (m/s^2 -> m/s - m) and this significantly exaggerates the noise of the accelerometer. The upshot is that using accelerometers to derive distance is fairly inaccurate.
Are you lowering the unit down the well, manually running it up the wall or what?
The device is handhold, I am thinking maybe I slaughter one of these or I just add stuff to it. Should be possible to get analog readings from it since it gives level of moist in a led-lighting kind of way. From green,, thru yellow to red.
When measuring I move it with contact to the wall. I do this pretty randomly actually but there is of course ways to change this. Maybe just move in one direction first, with short "burst", then move up a dm and continue.
Position doesn't need to be 100%. But needs to be in decimeter range maybe.
I can move the sensor fast as my hand, with pauses for measurement. Is there a way you think? Maybe accelerometer isn't the way?
Thanks for help.
Both ideas sounds doable really.
Since I am a newbie I think ps2 idea sounds absolutely simplest.
Do you guys have any kind of idea how to do this? I will of course search forum/web for help. A tutorial and crash course in arduino is something I have to get to aswell!
I don't get the "male" mouse thing? This is with a rolling ball?
Optical mouse is easy, just buy one for the purpose.
Guess the programming will be the tough part!
Limpa:
Do you guys have any kind of idea how to do this?
That is why I specified the PS/2 interface, you will find tutorials and/ or libraries on doing that.
I did mean to mention that it may or may not be appropriate to look for an analog output on your humidity sensor if it displays these as a bargraph - depends on how integrated the design is - it may be an ASIC that only drives the LEDs.
Limpa:
I don't get the "male" mouse thing? This is with a rolling ball?
Umm, yes!
Limpa:
Optical mouse is easy, just buy one for the purpose.
I'll leave you to guess why I refer to optical mice as "female". XD
It isn't so easy to find specifically PS/2 (optical) mice sold nowadays. It may have been a point of inspiration that I was just washing some mice that I have picked up at "garage sales" over time. Fairly good - if not immediately reliable - source of spare mice.
You guys use a lot of words I don't know!
So, I'll try find a ps2 optical one. Is this your word of advice? I just needed to see if this was possible and for me doable of course!
Where so I begin?
About the sensor being analog I don't know how to find out. I guess I will have to take one apart first of all.
Or should I try to get a position tracking thingy going first maybe?
Can I be only one who wants to do position tracking wth arduino?
I am thinking might be easier for me, as newbie, to start with accelerometer. I am thinking, move a bit, push button to record from sensor, move a bit, push again.
Would be doable you think?
Personally I think it will be difficult to get useful position data without some sort of external position reference. For example a mouse would lose its position as soon as it was lifted from the surface and it would be very tiring to scan a mouse over an entire wall without lifting it for a moment. Also, how would you deal with obstructions such as shelves or electrical outlets?
In theory one could have an X and Y location sensor temporarily fixed at the edges of a wall and the ceiling and the handheld device could determine its position relative to them. But I have no idea how you actually implement that.
