Video Camera

For my project I want a Robot that I can drive using my computer, it can't be Wi-Fi based, I will not have access to internet. Does anybody have a project like that? It also needs to have a camera.

Just mount the computer on the robot.

No no, its will kind of be like a EOD Robot

AJ_M:
No no, its will kind of be like a EOD Robot

You really need to explain in detail what you want to do. What is an EDO robot?

EOD usually stands for Explosive Ordinance Disposal.

I just want to be able to control a robot via wireless signal, and also see through a wireless camera on the robot.

An approach to consider.

http://www.lynxmotion.net/viewtopic.php?f=20&t=6343

AJ_M:
For my project I want a Robot that I can drive using my computer, it can't be Wi-Fi based, I will not have access to internet. Does anybody have a project like that? It also needs to have a camera.

First off - you don't need internet access to set up a point-to-point wifi link; you might want to educate yourself on networking and wireless networking fundamentals, because honestly, using wifi will likely be the easiest method.

Otherwise you could do something like this:

(2.4 GHz or 900 MHz) wireless camera (on robot) -> wireless signal -> (2.4 GHz or 900 MHz) video receiver -> video capture device (USB or other) -> PC

Custom code on the PC would then handle viewing the video, integrating it with your control/command/telemetry tracking system, etc. This code would also interface to something like:

XBee or "virtual wire" TTL serial transceiver -> wireless signal -> XBee or "virtual wire" TTL serial transceiver -> Arduino on robot

The Arduino, of course, would be connected to the motors/sensors, etc - and would take commands from the PC over the wireless link, and would also uplink any necessary telemetry back to the PC custom control/command/telemetry tracking software.

See how complex that is? Also note that for an EOD system, we haven't even talked about encrypting the signal. Whereas for a standalone 802.11 system:

IP Camera ---> WiFi router/AP <---> WiFi wireless signal <---> WiFi Card or router/AP <---> PC (w/ custom control/command/telemetry tracking software)
Ethernet Arduino <---^

The IP camera would supply a simple MJPEG stream via a particular IP and port; the Arduino would be controlled and communicated with via another set IP and port (you would want the IP and port to be static, or at least a fixed DHCP assignment from the on-board router). If your router on-board the robot was beefy enough (or if you added an on-board PC - like a nano-ITX board, or a beagleboard, maybe - heck, even a Raspberry PI), it could actually host the command/control interface right on-board; set up the control software using DHTML (lots of good stuff for this, BTW, especially if you go for HTML5 tags - jack in a nice admin panel, some AJAX, a bit of JQuery).

...and for encryption? Use WPA2 for base testing; if you want better security, add SSL (with a home-genned cert) to your web server hosting the interface; and if you are really paranoid, tunnel it all over SSH or something. Basically - all the issues you'd run into with the first solution, can be more easily handled in software with the second.

That said, the second solution may or may not be as robust as the first solution; it will all depend (whichever solution you go with) on what you select for hardware. For instance, the second solution might be downright flaky over distances greater than a hundred feet or so, depending on obstacles, buildings, etc - if you used consumer hardware. If you went with professional hardware (and maybe some amplifiers, antennas, etc) - that could be made better. You'd face similar problems with the first solution as well, depending on what you used.

EOD usually stands for Explosive Ordinance Disposal.

Unless you are writing to files. Then, it's End Of Data. Which, generally, is a lot safer.

I did it like this

the video link is a 2.4Ghz digital security camera that doesn't mind 2.4Ghz XBee's.

If you use a 2.4Ghz analog link you will have to use the 900Mhz XBee.

do you use 3G robot camera? it built-in web server, allows remote access from any web browser for live image viewing and monitoring

It's a digital security camera, I have not had a chance to investigate the protocol.

Nut it does "play nice" with the 2.4Ghz XBee link, except at extreme range, then the video Tx starts to "swamp" the XBee Rx.

I'm going to use a 900Mhz XBee link, with a 2.4Ghz analog video link.

Sounds like you might want to investigate skew planar / virivent antenna for your transmission issues.

That was something I thought about trying.

There is an Antenna manufacturer in Echunga! They doe all kinds of amazing stuff.
The owner is a great guy, anything I take to see if it "in tune" or when I need a spectrum analyzer, he does it gratis, just because it's cool and he is on the same page as we are!

His suggestion of getting the antennas at least a couple of wavelengths of the ground was when I started getting nearly 1km of range!

When we had a look with the spectrum analyzer, the security camera's output was a "mess"!
He was amazed the XBee could receive at all!

Some long range wifi stuff:

http://www.wifi-toys.com/wi-fi.php?a=articles&id=91

Two particularly good articles on here for antenna creation

It's often a bit more than just range you need to consider. A cloverleaf with a high gain patch will also cut out cross polarity interference, something you especially need to consider with a moving object.

Being close to the ground presents a different set of problems than a flying platform.

Im always surprised that cloverleaf antennae stay in shape on an aircraft!!!

A cloverleaf WOULD look pretty cool on a rover!

:slight_smile:

You're right, there's more reflected wave forms on the deck. More of a reason to use circular polarised antennae :wink:

So far as staying in shape is concerned, there's only really one chance for it to get bashed in a flight unless you're doing it wrong, lol.

Personally I'd go for a virivent, they "apparently" perform better than a Clover and have a flatter profile.