Remote controlled CCTV surveillance system - Arduino based

[Gina]

Latest circuits. The relay circuit shows diodes across the coils but I don't think these are necessary as the Arduino has push-pull outputs.

[yesyes]

driving relays directly from the Arduino outputs? I'd put a small transistor in between....

[Gina]

I know a driver transistor is the standard method but these are only PCB micro relays and take just 27mA at 5v. The Arduino is specified as capable of sourcing or sinking 40mA on each digital pin. There would be one relay on continuously and one other on for a short period (a few seconds).

[Gina]

Been thinking I might use a naked ATMega328P in the relay unit rather than a Nano, like I'm doing with the remote control. I have USB to serial 5v TTL adapters and the processor only needs PC connection for uploading the sketch. I could use a couple of ULN2003s to drive the relays as suggested in another thread. Maybe driving an inductive load directly is not such a good idea.

[pete_l]

Latest circuits. The relay circuit shows diodes across the coils but I don't think these are necessary as the Arduino has push-pull outputs.

For the sake of a couple of pennies, I'd probably keep them in.

[Macavity]

Ah, the Arduino... A brilliant solution looking for an application?

But I too muse on multiple video cameras. As I move to remote scope control, aside from the MAIN (Watec) video camera, thinking about finder scope cam, mount position monitoring cam, remote control of observatory lighting etc. etc.

Have laid in a couple of 8-core screened (30m) "alarm cables" (useful stuff!) from lounge to observatory just in case...

[Gina]

Here's the latest relay box circuit.

[Gina]

Ah, the Arduino... A brilliant solution looking for an application?

But I too muse on multiple video cameras. As I move to remote scope control, aside from the MAIN (Watec) video camera, thinking about finder scope cam, mount position monitoring cam, remote control of observatory lighting etc. etc.

Have laid in a couple of 8-core screened (30m) "alarm cables" (useful stuff!) from lounge to observatory just in case...

I bought a reel of 6 core alarm cable some time back and I shall be using this to feed power to cameras, video back and DC motor control for the camera direction. I am replacing some cables that have been eaten by the goats and also rats. In fact it only needs 4 wires - Gnd, 12v, motor, video.

[Macavity]

Ah, that's what I need, some "5V micro relays" (Come pre-assembled in significant numbers too)!

http://www.amazon.co...e/dp/B005WR734M

Was racking my brains over switching a multi-channel mixture of TTL and Analogue signals... quad demultiplexers(?) ...bi-directional CMOS analogue switches(?). But with limited knowledge of the precise nature of the signals a simple group of relays could avoid expensive mistakes.

[Gina]

These are the chip kits I'm using - http://www.ebay.co.uk/itm/171069403348

[Gina]

Although I'm looking into both parts of this project viz. the camera control unit and the remote control, I shall start by getting the camera control working on it's own using a wired connection to a simple control box in the house, in the same way I've been using remote wired control for focus in my observatory. ie. a voltage on the wire read by the Arduino at the other end. Meanwhile, I can check out the radio tranceivers using two computers and USB to 5v TTL serial adapters. And also look into running the Arduino or rather ATmega328, at minimal power.

[Gina]

Before it gets too hot this morning I'm going round the currently fitted camrea/motor units doing maintenance. Some of the motor/gearboxes aren't working due to rust and dirt and I've been dismantling these and cleaning and oiling. I have a couple of the motor/gearboxes unprotected and I'm now fitting them in plastic boxes (food containers) that I got from a local cheapo shop for a pound or so. These are alright indoors but I've found they disintegrate in sunlight. I have some proper outdoor weatherproof (IP56) boxes on order - http://www.ebay.co.u...984.m1439.l2649 for the outdoor cameras.

The present motor/gearboxes have 1.5-3v DC motors which take around 300mA at 1.5v. I was thinking of changing these to the 12-24v version to reduce the current but I think I'll keep these and see how it goes with the new wiring (motors are currently wired up with bell wire and run from 3v AC with diodes to provide half-wave rectification). No point in fixing something if it ain't broke The idea of replacing these with mini servo motors I have also rejected.

I've been looking at connectors to plug the camera cables into the control box. The current system is a mess with phono connectors for video and motor wires connected with a chocolate block connector. I think I would prefer to have a single cable from the control box to each camera with one plug each. Surfing ebay, the cheapest decent connectors seem to be SpeakON loudspeaker connectors which provide the 4 pole connection. Plug - http://www.ebay.co.uk/itm/190866749296 Socket - http://www.ebay.co.uk/itm/200940692684 These seem suitable (unless someone has any other suggestion).

[Gina]

Here are some photos of the motor/gearbox units with camera and trying an idea for a stop and sprung slipping clutch to prevent the camera being rotated too far.

[Gina]

Been looking at the specs of SpeakON connectors and really they are overkill for this application. Rated at 40A and designed for thick cables/wires, they are designed for high power loudspeaker systems.

This is an alternative http://www.technobotsonline.com/connectors-and-headers/chassis-connectors.html but I think these are like the miniature XLR connectors and may be rather small for connecting up. Standard size XLR connectors are considerably more expensive and with the number I shall require makes a difference. OK so not a lot compared with astro kit but...

[Gina]

Layout for the camera control unit.

[Gina]

The connectors came from Technobots this morning and they look just the job

[DIYASTRO]

Gina,

Those chassis connectors I think are Yaesu style mic.connectors. I use them a lot esp 8 pin version, only thing to be carefull of is the pins in the plug. When you come to solder them you will see that they are quite thin and fragile esp the 8 pin ones. The pins on the skt's are much thicker and require a bit of extra heat from soldering iron to fill the bucket with solder.

Nice connecters .

Boyd

[Gina]

I see what you mean about the plug connections, yes, they'll need some care with the soldering. The larger solder buckets are similar to standard XLR connectors and I'm used to those so no problem there.

[DIYASTRO]

Gina,

I am sure that you will remember anyway but be sure to solder pin 8 on the 8 pin plug version FIRST (same with 5,6&7 pin) or you will find that as the last connection you wont get the soldering bit near it! Oh, also plastic sleeve inside the plug make sure that is slipped over the cable with the rest of the plug before soldering !

I am sure you will find these connectors good to use.

Boyd

[Gina]

I've been looking into this again - the whole project - a complete redesign.  The ability to fabricate any plastic part that will fit in a 200mm cube extends my options enormously.

In using the current CCTV system a couple of major points come up - principally the ability to alter the vertical angle as well as the horizontal would be an enormous advantage and may even mean I could cover as much with fewer cameras.  Control could be with a joystick rather than buttons - a more user friendly system.  The current implementation and the proposed version has problems with limiting the rotation effectively.  With 3 things to select per camera (video, horizontal and vertical movement) 2 pole relays won't do it.  I'm thinking of installing a CCTV camera in my scope room so that I can watch that the does what I want and the scope is pointing in the right direction

With the low cost of ATmega328P Arduino type chips and stepper motors + ULN2003 driver chips I'm thinking of using microprocessor control at the site of each camera.  That keeps the number of wires to each camera position the same at 4 viz. Gnd, +12v, control and video.  One analogue line will control all functions.  Rotation limiting will be much easier - simplest probably magnet and relay.

I'll post more later...

[Mr TamiyaCowboy]

I've been looking into this again - the whole project - a complete redesign.  The ability to fabricate any plastic part that will fit in a 200mm cube extends my options enormously.

In using the current CCTV system a couple of major points come up - principally the ability to alter the vertical angle as well as the horizontal would be an enormous advantage and may even mean I could cover as much with fewer cameras.  Control could be with a joystick rather than buttons - a more user friendly system.  The current implementation and the proposed version has problems with limiting the rotation effectively.  With 3 things to select per camera (video, horizontal and vertical movement) 2 pole relays won't do it.  I'm thinking of installing a CCTV camera in my scope room so that I can watch that the does what I want and the scope is pointing in the right direction

With the low cost of ATmega328P Arduino type chips and stepper motors + ULN2003 driver chips I'm thinking of using microprocessor control at the site of each camera.  That keeps the number of wires to each camera position the same at 4 viz. Gnd, +12v, control and video.  One analogue line will control all functions.  Rotation limiting will be much easier - simplest probably magnet and relay.

I'll post more later...

maybe thought of using arduino coupled with a nintendo wii handcontroller ( over-ride the pan/tilt function of system) 

In the rc world we had been using servos as pan/tilt platforms but we found them lacking a bit.

Now we run low KV brushless controllers and motors, very smooth and slow/fast when needed.

servos also need to be rated for there strength its not unsusal to see 5kg servos running pan/tilts

i am unsure if our rc TX rx signal senders will work for your purpose, we tend to only use two cameras ( pilots cam and passenger cam)

but we use very small 12v video rx/tx gear coupled to 420 tvl and upwards cctv cameras. 

for quickness, i installed a Arduino bluetooth breakout into my flight controller brain ( basicly an arduino that flys).

allows me to write and read to and from the system to an andriod phone/lappy/pc (10m is fine you may want more range ).

You may find some Useful CODE in google Multiwii 

you may also find the multiwii nunchuck/controllers useful.

they have ITG3200 gyros , and accel sensors fitted inside and arduino see's them 

so a few old controllers could be hacked to give you gyro and accel sensors

camera could become auto smart and not over rotate.

[Gina]

With plenty of spare time available and needing plenty to do I am resurrecting several of my previously suspended projects.  This is one of them

I have been thinking about the whole overall design and principles involved with the plan of simplifying things.  This follows on from post #70 above using ATmega328P chips to control each camera.  I have been looking at ways of reducing the mass of wiring required by changing from a star type wiring system to a ring (like a ring main electricity distribution system) or daisy-chain. 

The video is probably better with individual coax cable feeding directly from camera to a central switching station though this is not carved in stone.  The control line could be changed to a ring/daisy-chain by selecting which camera unit is to be controlled (only one camera will be controlled at a time).  One method of doing this would be by using the 1-wire DS2413 switch.  Each 1-wire device has a unique code so many can be controlled by one line (plus ground).  Each DS2413 has two switches thereby providing 4 different states.  These can be translated to Left, Right, Up, Down for the camera direction control.

This means that three of the wires could be run from camera to camera in a chain viz. Gnd, 12v, 1-wire.  The 12v will supply the camera and and the ULN2003N and stepper motors but will need dropping to 5v to supply the ATmega328P (an Arduino board has a voltage regulator chip but this is not included in an ATmega328P chip).  Fortunately the microprocessor chip doesn't need much power

So camera control is handled by a simple 1-wire network but we still have to select which video line to connect to the displays.  In view of the low impedance (usually 75 ohms) the easiest way is to use relays (as before) run from an Arduino or ATmega328P chip.  Another way would be to terminate each video line with a resistor and select with a MOSFET chip feeding into a video amplifier chip to drive the monitors.  Admittedly, this would be a more elegant solution

[Gina]

I've been working on the mechanics to control the pan & tilt for the CCTV cameras, mainly a heavy duty mounting for a large CCTV camera with lots of IR LEDs giving a 30ft range.  This will replace the current camera that covers the yard and main gates.  I think I now have practically finished the design for this and will post particulars and photos shortly. 

Meanwhile, I have been working on a smaller drive and support that will take "board cameras" for covering less important areas.  These will have plastic domes for weather and dust proofing rather than using weatherproof cameras.

This design uses concentric cylinders to connect the two stepper motors to the camera in a similar way to  those used in analogue clocks to drive the hands.  The outer cylinder will carry the frame for the camera which in turn carries the yoke that gives the tilt motion.  The latter is obtained from the vertical axis second cylinder by bevel gears that drive the yoke. 

The inner cylinder provides the main bearing and is fixed.  The hole through the middle will take the cable from the camera with power and video.  Some cameras will want 360 degree continuous rotation and slip rings will carry camera power and video to permit this.  I have yet to work out how I shall do it though.

Here is a screenshot of the SketchUp model showing the "bones" of the design. I have yet to add the two stepper motors with pinions that drive the large spur gears.

[tekkydave]

1-wire is brilliant. All my weather sensors are 1-wire and the farthest away is about 50m with no extra power supply.

Homechip do some good 2-channel digital i/o modules based on the DS2406

http://www.homechip.com/index.php/1-wire-controllers/sensors/d2p-2-channel-digital-i-o-1-wire-card-pullups-no-connectors.html

[Gina]

Thank you Dave   Though rather than using ready made up modules I expect to use the bare chips.  Actually, I need 5 states as it needs to include OFF ie.  OFF, left, right, up, down.  So those modules or the DS2413 will not do.  Either 2 of them per camera or 1 DS2408 would be required.  Coincidentally, 2 x DS2413 is within a penny of the cost of 1 x DS2408 (2 x £1.56 = £3.12 and DS2408 is £3.13).

And yes, my weather station is practically all 1-wire too   I agree - 1-wire is brilliant