can somebody help me out? i trying to build a fully motion automatic cat door opener. i don't have $400 for a pre-built one plus $50 for 4 collars. i want the door to slide up&down or from side to side. one of my cats don't like to use the door, but it does a great job at keeping smell and flies away. but i don't much about programing codes, to arduino, pir, servos etc.
with the following parts:
Ideal Pet Products 58000 medium cat door
1 arduino Duemilanove microcontroller
1 Sensor Shield add-on card for Arduino Duemilanove board
2 Infrared PIR Motion sensor modules
1 Digital Servo
some jumpers
not sure what your question is, but assuming you are asking on some feedback to the parts you plan on using:
marquita188:
petmate medium cat door
whatever that is... I assume it'll do the job
1 arduino Duemilanove microcontroller
spot on.
1 Sensor Shield add-on card for Arduino Duemilanove board
these are handy, but not really necesary. I have one of those and find that I dont really use it. if you want to save money, dont buy this. you dont need it. (if you do buy it, it does make things a bit easyer for beginners)
yep. but. how will the servo move the door? its sometimes not that easy getting the motion which you want out of a motor.
If I where you, I would take apart an old CD drive. You might be able to use its edject mechanism to build a sliding door.
some jumpers
Yep. And a breadboard.
Hope this is of some help. if not feel free to ask specific questions. Also post links to the products you are considering. A servo can mean all kind of things and so can a PIR module. If we know specifically what you are considering, then we can give you real advice.
Cheers
p.
(oh and look into RFID. You might not want to use IR, but an RFID chip to activate the door. That way you can prevent squirrels or snow or leaves from activating your door.)
these are handy, but not really necessary. I have one of those and find that I don't really use it. if you want to save money, don't buy this. you don't need it. (if you do buy it, it does make things a bit easier for beginners)
ok, so you think a twigs would work better than Parallax PIR Sensors? and how do you connect these to the arduino?
yep. but. how will the servo move the door? its sometimes not that easy getting the motion which you want out of a motor.
If I where you, I would take apart an old CD drive. You might be able to use its eject mechanism to build a sliding door.
OK, how would you use the CD drive? i have a bunch of these laying around.
Yep. And a breadboard.
Hope this is of some help. if not feel free to ask specific questions. Also post links to the products you are considering. A servo can mean all kind of things and so can a PIR module. If we know specifically what you are considering, then we can give you real advice.
Cheers
p.
(oh and look into RFID. You might not want to use IR, but an RFID chip to activate the door. That way you can prevent squirrels or snow or leaves from activating your door.)
how do you program the arduino to do what you want it to do? do i need a PC to use it?
ok, i forgot to tell you that the door is for the litter box, not outside. because my cats stay indoors.
A servo might be overkill for an application like this. If you've never done anything like this before you might look at controlling a simple DC motor with an h-bridge so you can reverse the direction of the motor.
Servos can be very accurate, but also very expensive, and there's a little learning curve on the programming side. Controlling a hobby motor might be an easier start.
You might also need to think about a gear system so you can get enough torque out of a small motor to lift a pet door.
marquita188:
ok, so you think a twigs would work better than Parallax PIR Sensors? and how do you connect these to the arduino?
a twig has three connectors. one goes to +5v one goes to an analog input and one goes to ground. The twigs, just like the phidget sensors and various other "bricks" are built so they can work with an arduino with as little hassle as possible.
The sensor you linked to on ebay requires 4.5V input and an output of 0 to 3v. Arduino outputs either 3.3v or 5v, and its input is designed to recieve voltage between 0 and 5 volt
So you can use that sensor, however you will have to create your own circuit if you want it to work as well as a phidgets sensor or a twig. These already have the additional circuit built in.
(I might be wrong with details, but you get the generall picture.)
OK, how would you use the CD drive? i have a bunch of these laying around.
Well, I often find it a bit tricky translating the motion of a servo to linear motion. Linear servos exist, but are quite expensive. You could also use a mechanical solution like in the video you posted.
I was thinking this: You know how CD-Drives cen slide the tray in and out?
Well basically that can be your door. Open the chassis of the cd-drive. In it you will find several small motors. One of them is sort of skinny and long (though this may be different between brands) and is connected to a drive system which opens and closes the CD Drive on the click of a button. Find yourself a motor shiled (google - there are tons) and connect the red and black leads which go to the motor you are interested to it. (I dont know what voltage they require - I would probably just try it with the Arduino set to 3.3V)
Alternatly you could also try to hack the pushbotton which activates the motor.
Then again, if you are not that into tinkering with electronics, maybe the mechanical motion translation is simpler for you. I dont know. I personally would start with the CD-Drive, and try to work from there.
Yep. And a breadboard.
!
how do you program the arduino to do what you want it to do?
you need to program it. the way to go about this is to go through code examples and find code which does sort of what you want it to do. Then learn how to tweak it. Eventually learn how to write your won code. The Arduino website has tons of ressources.
do i need a PC to use it?
You need a computer to program it. However, once that is set up, you can use the Arduino as a standalone device.
ok, i forgot to tell you that the door is for the litter box, not outside. because my cats stay indoors.
If it is indoors I would consider this sensor:
it activates at proximity of 10cm and gives a simple on or off symbol. Should be very easy to use.
Alternatly consider:
in combination with
this will get you an analog reading between 0 and 1024 which lets you be a bit more flexible.
phidgets also has a linear servo, but its rediculously expensive:
OK gotta run.
good luck
(btw. the sensors I recommended are for indoors use only. sunlight does not become them.)
fkeel:
Well, I often find it a bit tricky translating the motion of a servo to linear motion. Linear servos exist, but are quite expensive. You could also use a mechanical solution like in the video you posted.
I was thinking this: You know how CD-Drives cen slide the tray in and out?
Well basically that can be your door. Open the chassis of the cd-drive. In it you will find several small motors. One of them is sort of skinny and long (though this may be different between brands) and is connected to a drive system which opens and closes the CD Drive on the click of a button. Find yourself a motor shiled (google - there are tons) and connect the red and black leads which go to the motor you are interested to it. (I dont know what voltage they require - I would probably just try it with the Arduino set to 3.3V)
Alternatly you could also try to hack the pushbotton which activates the motor.
Then again, if you are not that into tinkering with electronics, maybe the mechanical motion translation is simpler for you. I dont know. I personally would start with the CD-Drive, and try to work from there.
can you give me step by step i just don't see what you are talking about.
if you want a sliding door, you can either buy a 90$ motor, or use a sliding mechanism which you already have.
Your hard drive slides open and close. thats the door opening and closing. so you replace the cd-tray with a "door" and mount it in your wall. You find the electricity leads going to your motor, and connect them to a arduino motor-shield.
That way you save yourself a lot of money, and possibly time as well.
Open up your cd-drive and take a look. I dont have time to write you a step by step.
It all depends upon how experimental it is, and what your preferred approach is. Maybe my Idea doesnt work for you. Its just a suggestion.
cheers
p.
Edit: Yeah. You get the idea. You can do exactly what they did in that video, just instead of an iron rod, you will be moving the door for your cat.
But its just a suggestion. There are many ways to do it.
if you want a sliding door, you can either buy a 90$ motor, or use a sliding mechanism which you already have.
Your hard drive slides open and close. thats the door opening and closing. so you replace the cd-tray with a "door" and mount it in your wall. You find the electricity leads going to your motor, and connect them to a arduino motor-shield.
That way you save yourself a lot of money, and possibly time as well.
Open up your cd-drive and take a look. I dont have time to write you a step by step.
It all depends upon how experimental it is, and what your preferred approach is. Maybe my Idea doesnt work for you. Its just a suggestion.
cheers
p.
Edit: Yeah. You get the idea. You can do exactly what they did in that video, just instead of an iron rod, you will be moving the door for your cat.
But its just a suggestion. There are many ways to do it.
yeah, but the motor on my CD drive don't look anything like that. it don't have red & black wires, or any wires coming out of it, just those ribbon things.
It looks like your CD drive has a stepping motor to move the read / write head. From a pile of scrap CD drives I had to make this project there were about a third of them like that. I had two with brush-less DC motors and conventional motors in the rest.
However, what they were talking about is the motor that opens and closes the sliding door or CD eject mechanism, I found all of these were DC motors wit an arrangement of slides and gears to change direction. Out of 25 CD drives I took apart no two were exactly the same, even those that were supposed to be the same brand so it is not feasible to provide step by step instructions.
Now I'm thinking, I'll just do the gravity way, by using the CD drive, tension springs, adjustable curtain rods.
but how do i jury-rig the push button on the CD drive?
I'm pretty new to this stuff to but why not use a solenoid (or something to that effect) instead of a servo/motor/cd-drive, i simple pull motion when power is applied then would only need to be connected via a hinge (not even for a sliding door) and not have a need for gears/pulleys or any of that stuff.
I'd be looking at diminishing the time taken and noise created for the door to open so as to not deter the cats from using it (I have a jumpy cat that will not use a normal cat door), the cd-drive could be a little slow to open the door as it takes a fair bit time just to open the tray which only moves a few inches. You also then only have a plastic gear which you could buy at Jaycar for next to nothing.
greywolf001au:
I'm pretty new to this stuff to but why not use a solenoid (or something to that effect) instead of a servo/motor/cd-drive, i simple pull motion when power is applied then would only need to be connected via a hinge (not even for a sliding door) and not have a need for gears/pulleys or any of that stuff.
I'd be looking at diminishing the time taken and noise created for the door to open so as to not deter the cats from using it (I have a jumpy cat that will not use a normal cat door), the cd-drive could be a little slow to open the door as it takes a fair bit time just to open the tray which only moves a few inches. You also then only have a plastic gear which you could buy at Jaycar for next to nothing.
whats solenoid? how can i make/build what's your talking about?
