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LongRangeTruck

FPV RC Truck

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Hello everybody!

I have been wanting to modify a RC truck for long distance operation with a first person camera view for years. I have never really had the time or (more importantly) the money for such a project. I graduate from college in August and thought this would be a good graduation presenet to myself.

I am going to scrap the Traxxas radio and build my own using a a Maxstream XBee-Pro Module. The website claimes ~1mile range. I will probably add a XTend Module that will turn on if the XBee looses connection. THe XTend is good out to ~ 40 miles at full power.

For video, what does everyone recommend? 900mhz or 2.54ghz. The transmitter will be at most 2ft high in an urban setting. I forsee horrible multipath issues. The XBee-Pro is at 2.54ghz and the XTend is at 900mhz.

I am hoping for ~1 mile range ground-to-ground in a residential area. Is that even possible? When I decided to research this project, I did not realize how expensive long range video transmitters are. From talking with a professor of mine, he predicts I will loose up to 80% of an advertised line of sight range in an urban setting.

This idea is still in the formulation stages currently. Any and all questions/advice is desired.

From searching through the posts on this forum, it seems that there is a lot of knowledge here. Thank you in advance for passing it to me.

- joseph Y. :)

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Hello,

I did this more like for fun - a sunday afternoon project. Nowhere near the range you want to achieve.

The link for some of the pictures I've taken are here:

Rammunition

I used a regular airplane radio to control the truck - the range is pretty good, and it even works behind structures. From the original truck I cleaned out the cheap electronics, and replaced it with a real servo for stearing, a real proportional speed controller, and a real full range R/C aircraft receiver.

The reason for this is that you require 2 extra channels for the FPV's servos.

The transmitter is Airwave 612 - 500mW, and the reveiver is Airwave as well, I used the GP patch antenna found on this site.

Here are some pointers you need to take in consideration:

- 2.4 Ghz video systems do not have good penetration. The range will be drastically reduced even if you are behind a garbage can... The same transmitter I use on my airplane flawlessly to fly around in a 1500ft circle it will give me less than 800ft on ground level - line of sight. If there are structures between, you'll loose it in no time. My street is about 300m (900ft) long, and if there are no cars arond, I can go to the end of the street and still have video, however as soon there is something between the receiver and transmitter the signal blacks out. Interestingly my radio still works with no problem.

- trucks are not like planes, trucks have tires, which go on bumpy road. THe video footage coming from a truck is very vibrating, disturbing to the eye, because of the road. Also because of the road there are additional vibrations added to the camera/transmitter/servos - which may black out your video without any other reason.

- for the long ragnge run, you need a way to be able to look behind you as well, sometimes you need to go backwards, or just simply know that there is somebody coming (a car) behind your truck. For this you will need mirrors or a way to rotate the camera backwards....

- what happens if your truck flips on it's back and it is a mile away from you? Mine is a monstertruck and as it is, it doesn't like high speed curves, it will flip over if you are not careful...

These points coming from me riding the above cheap Rammunition quite a few times around the neighbourhood, i hope it gives you some pointers as well.

Ox.

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Thanks for the tips.

- 2.4 Ghz video systems do not have good penetration. The range will be drastically reduced even if you are behind a garbage can... The same transmitter I use on my airplane flawlessly to fly around in a 1500ft circle it will give me less than 800ft on ground level - line of sight. If there are structures between, you'll loose it in no time. My street is about 300m (900ft) long, and if there are no cars arond, I can go to the end of the street and still have video, however as soon there is something between the receiver and transmitter the signal blacks out.

That seems to be the general view I seem to be finding about 2.4Ghz. The truck will have to use 900Mhz for the video. That will interfere with the data modem I assume, or vice versa.

I used a regular airplane radio to control the truck - the range is pretty good, and it even works behind structures. From the original truck I cleaned out the cheap electronics, and replaced it with a real servo for stearing, a real proportional speed controller, and a real full range R/C aircraft receiver.

The reason for this is that you require 2 extra channels for the FPV's servos.

I plan to use a wireless serial link for control. The truck will have many more features in the end ...

- trucks are not like planes, trucks have tires, which go on bumpy road. THe video footage coming from a truck is very vibrating, disturbing to the eye, because of the road. Also because of the road there are additional vibrations added to the camera/transmitter/servos - which may black out your video without any other reason.

Yah, I have though about that. My friend and I were trying to think of a small "steady cam" setup to isolate the camera.

- for the long ragnge run, you need a way to be able to look behind you as well, sometimes you need to go backwards, or just simply know that there is somebody coming (a car) behind your truck. For this you will need mirrors or a way to rotate the camera backwards....

The camera will be mounted above the truck, essentially on a 6" upright with 360 rotation and 270 tilt. Now that I think about the raised camera platform and the steady cam, I do not know how to mount it.

- what happens if your truck flips on it's back and it is a mile away from you?

uhh..... :unsure: ... didn't think about that...?

- joseph Y.

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That seems to be the general view I seem to be finding about 2.4Ghz. The truck will have to use 900Mhz for the video. That will interfere with the data modem I assume, or vice versa.

900Mhz in the rural area is quite crowded. Check on 1.2Ghz, that has much better penetration and almost no devices on that frequency. You will have to check the frequency chart of your country if anything in that range is allowed. Also at the range you are talking about - you will need quite a bit of power - you will probably need to aquire a radio amateur (HAM) license.

Yah, I have though about that. My friend and I were trying to think of a small "steady cam" setup to isolate the camera.

The camera will be mounted above the truck, essentially on a 6" upright with 360 rotation and 270 tilt. Now that I think about the raised camera platform and the steady cam, I do not know how to mount it.

Steadycam on a 6" stand? How about flip-flopping/bending of the stand when riding on bumpy road?

Also I uderstand the 360 degrees pan, but tilt 270? What would be the practical function of that? When you look backwards, over 180 everything would be upside down...

No offense but somehow the steadycam on a 6" pole idea on a moving truck does not compile for me...

uhh.....  ... didn't think about that...?

The pole for the camera (with the camera on top) raises the CG of the truck (depending on the weight of the camera and how stiff the pole is) and that would make the truck flip over even easier...

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Many more features ...

This idea was kick started recently by a robotic competition I participated in recently. We had to pickup and deliver colored coke cans. All possible locations were linked by black lines on a white course. We used IR sensors for line following. On the drive back, we talked about using a camera to find the cans. Essentially, the robot would locate and deliver the cans in the same way a person would. The would visually look for the cans. Once it found the cans, it would look at the ground and follow the black lines to the delivery destination. This idea would require ALOT of video processing work. Since I wanted to build a FPV RC Truck anyway, we thought my project would be a good test bed to devlope the image based coke can finding robot.

What we want to create is an autonomous robot that when placed in an "unkown" environment, will drive around until it finds its object, a red kick ball for example. Once found, it would travel back to its starting location. We are going to convert the Truck to differential drive. This way, we can remove the steering servo and simplify some other issues. Also, differential drive has a zero turning radius, making it very manuverable. The ~40 mile transciever I mentioned earlier is so the robot can send back GPS data, compass heading, battery life. If the bugger would haywire, it could end up anyway really. The video transmitter was added so we could see what it sees for real time debugging.

Since I was going to be dropping the cash for all these items, I want the Truck to work like a FPV Truck first. This would verify all the low level control systems necessary for autonomous operation. Also, the basic idea of a FPV RC Truck is something I have wanted to do for years.

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Check on 1.2Ghz, that has much better penetration and almost no devices on that frequency

Never thought about the frequency. I will look into it. Thanks!

Also at the range you are talking about - you will need quite a bit of power - you will probably need to aquire a radio amateur (HAM) license.

I predict power consumption to be a real issue. Is getting a HAM license difficult?

Also I uderstand the 360 degrees pan, but tilt 270? What would be the practical function of that? When you look backwards, over 180 everything would be upside down...

From horizontal, -90 to +90 would be all that is needed. I was thinking -90 to +180, but the last 90 degrees is just redundant (and upside down). I do not know why I missed that. Thanks

No offense but somehow the steadycam on a 6" pole idea on a moving truck does not compile for me...

Me neither. I did not think about those two ideas at the same time until you mentioned it.

The pole for the camera (with the camera on top) raises the CG of the truck (depending on the weight of the camera and how stiff the pole is) and that would make the truck flip over even easier...

I was planning on using on the little cameras used for FPV planes. Would that much added weight be enough We modified a friend's Truck to differential drive and it widened the truck by 4" or so. It improved the stability significantly.

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I predict power consumption to be a real issue. Is getting a HAM license difficult?

Well, depends on where you live. Canada is not that difficult, you have a total of 700 questions with multiple choice answers, out of which you get a random 100. The latest is that you have to know the correct answer to 70 of these... And the questions sometimes are really getting into the details of the HAM frequencies, bandwith, electronic devices which are used, components, calculation and regulations...

I was planning on using on the little cameras used for FPV planes. Would that much added weight be enough We modified a friend's Truck to differential drive and it widened the truck by 4" or so. It improved the stability significantly.

Depending on the type of the camera you buy - it can be a simple and lightweight board camera (around 50 grams) - but then all the components are exposed - to a metal case weatherproof camera which can be around 100-150grams - that weight has to be take in consideration when designing the pole. The servos also have a little weight.

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I did some quick searches for 1.2Ghz video transmitters. I am not really finding anything that doesn't seem "ebay cheap."

I live in the US.

Edited by LongRangeTruck

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check out http://www.gowiththeshark.com/ - Greg the owner was looking also into the 1.2Ghz frequency range for the US. Send him a message from the Contact Us page, he did a proper research on this frequency, maybe he can give you some pointers.

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About the vibration issues of a cam on an RC car, if you waste money on a cheapie truck which only has spring suspension then yes you'll get a very jumpy picture, you need an oil dampened suspension truck, for starters without the dampening you have less control of the car on bumpy surfaces and with dampening you gain more control and a much smoother picture from the camera.

Even with a 1500mW AV transmitter on my Tamiya TLT-1 the picture dropouts occur too easily, I'm kinda jealous of the FPV plane flyers who can use a very low power AV transmitter and achieve incredible transmission distances.

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The truck uses "Traxxas Oil-Filled Ultra Shocks." Hope those are good.

Even with a 1500mW AV transmitter on my Tamiya TLT-1 the picture dropouts occur too easily

Could you provide more info about your transmitter? What kind of "consistent" range do you get with it? Thanks

I'm jealous of the FPV plane flyers too.

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I got it off eBay a long time ago and the particular one I have isn't sold anymore, there are other 800mw, 1000mw & 1500mw 1.2gbz AV transmitters but most are from a seller called USEEK and annoyingly none of their cameras & transmitters have audio.

I don't know how to gauge the range of it because I have some RC inteference and can't get the car to go all that far, I suspect the power of the AV transmitter is causing the glitching but I haven't really given it much testing - FPV with my RC car is just a fun time wasting thing I haven't put a heck of a lot of effort into it, mainly because of the short range issues even with a powerful transmitter.

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Hello everybody!

I have been wanting to modify a RC truck for long distance operation with a first person camera view for years. I have never really had the time or (more importantly) the money for such a project. I graduate from college in August and thought this would be a good graduation presenet to myself.

I am going to scrap the Traxxas radio and build my own using a a Maxstream XBee-Pro Module. The website claimes ~1mile range. I will probably add a XTend Module that will turn on if the XBee looses connection. THe XTend is good out to ~ 40 miles at full power.

For video, what does everyone recommend? 900mhz or 2.54ghz. The transmitter will be at most 2ft high in an urban setting. I forsee horrible multipath issues. The XBee-Pro is at 2.54ghz and the XTend is at 900mhz.

I am hoping for ~1 mile range ground-to-ground in a residential area. Is that even possible? When I decided to research this project, I did not realize how expensive long range video transmitters are. From talking with a professor of mine, he predicts I will loose up to 80% of an advertised line of sight range in an urban setting.

This idea is still in the formulation stages currently. Any and all questions/advice is desired.

From searching through the posts on this forum, it seems that there is a lot of knowledge here. Thank you in advance for passing it to me.

- joseph Y. :)

The post looks old, I was wondering how you made out with this project. I've been doin FPV in my emaxx for about a year now,,it's been alot of fun. Hope your project is coming along. Here is a picture of my platform, the camera system is not installed in this picture, but I have videos.

http://www.vimeo.com/597535

post-3219-1200338935_thumb.jpg

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Here is a picture from google earth. The red circle is my house. The yellow lines are the log trails we follow away from the house and all in between. The purple line is the river, we made it down once but my partner walked down next to it in case we lost range. We didn't but it was a little sketchy Could have lost signal at any moment so we are looking into amps for the transmitters. For video we already have repeaters in the works and that are tested and work good. Just need to order another setup and enclosurs.

post-3219-1200339328_thumb.jpg

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