xanboo/homesite laser break beam sensor
The problem is, I have a bunch of Motorola Homesight cameras and sensors, but none of them have lasers!
This project documented the trial, failure and success of the spare parts I would not use to build the laser sensor when identifying homemade sensors with Motorola Homesight software.
Motorola Homesight consumer home security product is a renamed version of the Xanboo product.
They are actually the same.
I will install the camera and install the laser with a plastic case.
Since I was going to destroy the camera, I decided to use a \"wired\" camera.
The wireless camera is still very useful for me, so I have set limits for my project. . . for now.
The water sensor will be used as a contact/non-contact interface in the home vision system.
I used the water sensor instead of the door or temperature sensor because I wouldn\'t lose anything if I fried it during the experiment.
I still find the door and temperature sensor useful.
The challenge is to build a small circuit that, depending on the presence/absence of the laser, can turn on or off the contacts of the sensor and squeeze the circuit into the battery box of the water. . . er. . .
I mean, laser sensors.
I should mention that I am going to use the laser that was torn off from the very cheap laser level I found at clearance for about $0. 50. Cheap.
When you process the laser, you will get what you pay.
This is a good thing in this case.
If you connect with a very powerful laser, you burn through your sensors, your house, your neighbor\'s house, and may ignite your sensors, your house,
Hell, you might be lucky enough to blind your intruder, or cut his leg off his knee, or burn the hair of a neighbor\'s cat, etc.
However, the risk exceeds the return, so it is only necessary to use a typical laser pointer laser. K?
I\'m not sure if I need to look into how to unpack the plastic on the camera.
This is very direct.
The camera case does have a lot of potential and I won\'t take advantage of it right away.
The lens hole is perfect for mounting the laser obtained from the laser indicator, laser level or laser.
The red laser has a lot of cheap sources, so I won\'t go there, but the laser will be emitted from that lens hole.
The white part below the lens hole is the infrared transparent lens for the camera passive infrared motion sensor.
Before I realized how useful this would be in the future, I tore it out. (
Invisible infrared laser. .
Eye safety may be a problem, though. . . )
So, take out the camera anyway and be sure not to damage the plastic box.
Then, glue the laser in place with hot glue.
Weld some longer leads to the laser, wrap the solder joints with tape or heat shrink tubes, and then feed the wires through the supplied holes and the neck of the camera housing.
By the way, the camera board itself is very neat.
The connector makes people think it\'s an s-
Video connection, but not.
Pins on the connector are used for composite video, analog mono audio, and motion sensor triggers (
Oh, power and ground).
Very useful, so I packed it up, tagged it, and then at some point later, threw it in the closet for other items. . . honest. . .
Will you believe my wife is turning her eyes over me now?
Okay, get back on track.
How to power the laser? Read on.
Well, one problem with the cable cameras is that they don\'t have any convenient power supply mechanism.
Fortunately, there is a removable stand with a wireless camera module with power jack, power switch and power LED.
If you open the bottom, it is very easy to modify this base to power the laser.
The problem, however, is that the wall skin that comes with the home vision device is 9v and 12 v.
Because the laser is running on the 3 Th. 3V (
3 button cells)
, I will have to take some action on this to avoid burning the laser before my intruder knocks on the door.
So how do you reduce the 9VDC source ~ 3. 3V?
Of course, you are using a voltage regulation circuit.
Did a little Google search and I found a tutorial on how to build a breadboard power supply.
Very suitable for my needs.
I adjusted a little to reduce the component and etched my own PCB (
Many tutorials on this topic), and, VOILA! a regulated 3. 3VDC source.
How to convert the water sensor into a laser sensor?
The underlying technology is the same.
This is a simple \"contact closure\" sensor that is triggered when the circuit between the two contacts is closed.
For the water sensor, the conductivity of the water turns off the circuit between the two probes and triggers the sensor.
For laser sensors, we have to figure out how to turn off the contacts with a bunch of red light.
Here\'s where you have to really focus on these pictures.
I\'m not a very descriptive person, so work with me here. . .
Figure 1 shows an open water sensor for tearing.
In fact, most of the sensors in this shape in the Motorola series are almost the same.
The difference is that the use of sensing technology is different.
So, there\'s a cool thing.
Did you see those door sensor pads?
If you connect them together with wires, the sensors will trigger, you disconnect them and they will reset.
See how it contacts the shutdown type system?
So how do you get the laser to bridge this gap?
With light sensor.
Go ahead and read on and I will show you how to build one.
So, I found these beautiful things called optical resistors on Radio.
Sometimes they are called light-sensitive resistors (or LSR).
They change resistance according to the amount of light seen.
Different light resistances have different values, so unless you\'re lucky enough to use the exact same light resistance as I do, I suggest you measure their high and low resistance.
I\'ll let you know in a second, but let you know first.
Let\'s Make a sensor with these guys.
First, look for a ballpoint pen.
You know, the one you stole from the hotel room?
The one you used in primary school? Yeah, those.
Open the pen and throw away the cap and ink cartridge.
This leaves the little plug on your tube and end.
Pull the plug down because this is where photoresistor is going.
Straighten the legs against photore and slide it into a tube of about 1/2.
Bend the optical tube lead around the edge of the optical tube.
Plug the plug back into its position and secure the two leads between the side of the tube and the plug. Congrats!
You just made a photoelectric sensor. A few notes. . .
First of all, the pen does not need to be black, but if not, then wrap a little electronic tape around the tube.
In fact, even if it is black, wrap some tape around the tube.
The idea is that only light from the end of the tube can reach the light resistance.
The white pen, in particular, will allow the light to pass through the side of the tube.
I have to stop because it will cause the wrong reading later.
Also, if you have a laser that is too powerful, it will burn out your light resistance.
Stick to the cheap laser indicator and you\'ll be fine.
Once this thing works reliably, I plan to try a shorter tube length.
It is not too flexible to have a 5 \"tube as a sensor.
With some adjustments I want to put it under 1 \"and in the camera. . er. . . laser head.
Now, the next part is important and I hope you have an ohm-meter handy. Grab your ohm-
Instrument, and connect it to the lead of the optical tube.
We will read the resistance of the optical resistor under the condition of complete darkness and laser irradiation.
Instead of putting your finger at the end of the sensor (
Your skin is really bleeding a lot of light)
Stick it up and throw it in the drawer. Take your ohm-meter reading.
This should be a very high number, so make sure your meter is set up correctly.
In full darkness, I have more than 2,000,000 ohms of the optical tube and more than my meter, so I call it 2 MOhms. Write it down! R-)
Update: The First Circuit is not working reliably for some reason.
I am testing the second circuit using a 3v relay.
A picture of the circuit has been uploaded, so please check.
I haven\'t built it yet, so please keep an eye on it and see what happens.
More information on how I can set it up in the next section.
Well, that\'s what you\'re waiting.
I saw you jump to the end except you.
You can connect it in two ways.
The laser and sensor on the same side, or the laser on one side and the sensor on the other side.
Either way works.
Let\'s talk about the pros and cons of each approach.
Lasers and sensors on the same side: Advantages: laser cameras and laser sensors can be powered from the same power supply.
Just put both around an exit and you can go.
The power switch on the laser can also turn off the power of the sensor. Nice.
This enables you to do something advanced, such as using a power module, to power the laser sensor only when a wireless camera sees the motion of the infrared sensor.
As an intruder, how do you want to go to a house when you approach, and only see the laser probe system itself. Too cool.
Cons: You need a mirror to bounce the laser back to the sensor.
It\'s not a big deal, but the mechanics of such things are a bit tricky.
In addition, the mirror can also distort the laser beam.
This is because most mirrors are reflected back, which means that the laser has to go through a layer of glass before it is reflected.
Also, the mirror can get dirty as a more practical thing.
I am using the mirror I \"borrowed\" from my wife and it seems OK so far.
I might replace it with something that is unlikely to cause me trouble.
Laser and sensor opposite: Advantages: no need to worry about the mirror, the distance of laser propagation is shorter.
Cons: Power supply is required on both sides.
You can power the sensor module with a designed AAA battery, but I haven\'t tested/calculated my modified current consumption yet, so it might go through the battery like crazy.
In the Motorola Homesight software, the water module was found and worked as expected.
In this case, the module displays \"dry\" when it is normal and \"wet\" when the laser is interrupted \". Sweet!