Hi guys this is my first post so I'm not sure if I'm in the right forum section, so sorry in advance.
Anyways, I am currently working on a college engineering project where we have to create a smart product that incorporates some type of sensor or system that detects something in the environment and responds in a certain way to fix a problem. The thing is, due to the current circumstances, instead of having a plethora of sensors available to me at my college, I am now supposed to use what sensors and devices I currently have available with me at my home. I do not have many sensors with me.
For my project, I was wanting to make an automated pet water bowl that detects whether the water bowl is full, and if it isn't, it opens a valve from the water line of my house and fills the water bowl until it is detected to be full again.
Since I am limited to the devices I have available to me, I was thinking of using a homemade conductivity sensor that I used for a project last quarter. In order to detect if the bowl was full, I would have a circuit connected to one of the digital pins of the Arduino, there will be two probes connected to the circuit that act as a gap between the circuit, whenever water bridges that gap, the circuit is closed and, after going through a 10k ohm resistor, it goes to ground on the Arduino.
This is a really drawn out story for my question, but I wanted to express my current situation to show that I don't have any other simpler ideas. So my question is, will the current from the circuit be enough to harm an animal or to even be detectable whenever they stick their tongue in the water. I think it would be harmless, but I wanted to double check on the concept of the system and the possible effects before actually testing it.
This is a task that easily solves by using a closed bottle and 2 plastic tubes. Make both tubes adopt the the bottle tightly. Make one tube slightly shorter than the other one. Apply the tubes to the bowl. The short tube will do the breathing for the bottle and as soon as it gets air water will flow down in the other tube.
Keep it simple...
Railroader thank you for your input, but for our project we are required to make our system run off of a sensor or some electrical device that connects to the Arduino. Also, I would like to connect it to my water line so it will have an unlimited supply of water. I might have misunderstood your explanation, but just wanted to clear mine up.
Oki. My "system" required manual filling now and then, not using the water line preasure.
Okey, You have a project that calls for giving an UNO something to do. What sensors do You have on hand?
Well the only sensors I have is a photoresistor, ir motion sensor and ir light, thermistor, and the conductivity/continuity sensor.
I could use the photoresistor or the motion sensor in someway to detect it, but I figured they would be less consistent than the conductivity sensor, and it would be easier to implement the conductivity sensor.
What about this? Use a float, a piece off wood, cork, to be a level sensor. Than detect that float using an IR or photoresistor. You will have to do some minor mechanical rigging.
Yes I thought about that and I believe it would work. This was my backup plan if the first one didn't work. Just curious though, do you think I should steer away from trying to use the probes from the conductivity sensor. I feel like that would be simplest, and I think it would be safe and consistent. I want to get someone's opinion on it though who is sure if it is safe or not. 5 volts and a 10k ohm resistor should be harmless right?
You could use a capacitive touch sensor that works for proximity and then could work without any contact.
If you use condutance sensors like digital pins make sure that both contacts are close enough then the current only flow between the contacts and are away where the pet will drink. Use resistors then the current will be very low.
Water conductivity will probably work for some time. Do some experimenting regarding the resistor value. It all depends of the conductivity of the actual water. However electrolythic phenomena will erode that sensor in the long run. Maybe it's okey in order to show up the proj.
I would not hook to the water mains - an unlimited water supply and maybe a bad connection that comes off and floods your home is not good - have also seen issues with hoses/tubes in industrial plants. A friend some years back had a plumber put in new piping and did not use a hose barb and only one hose clamp - end result was a lot of water and ruined things in the basement. I would use some sort of water bottle to store the water. Then as a bonus put a level sensor in the storage tank with an alarm - impress your instructor with the double safety.
If you have a small pump that can recirculate the water in the bowl and a sensor to detect the cat - turn the pump on - I have read that cats like running water to drink
@saildude
You are right. Line water can be very destructive, as well as mains. However this is obviously a school project and main water is soon disconnected after testing.
