This will be about my adventures in RC car FPV.  Who knows how long I will be interested in it lol.  

The background is I saw this RC tank looking thing at Marshals (discount store) for like $20 and thought ... camera!!  I slapped a BetaFPV AIO camera vtx on it that I thought was broken; jumped the video out and video in leads; soldered a tiny whoop connector to it and threw on a 1S lipo.  We had so much fun!!

So decided to step it up a notch ... 



I know nothing about RC cars but decided on this 1:18 scale "Yeti Jr" made by a company called Axial.  It was an "RTR" (same as our "RTF" lol) kitted with a 2-channel Spektrum.  Lol @ 2 channels.  Coming from quadcopters, these things are super rudimentary because they really don't have to be complicated.  Gas and steering lol.  But then you don't have all the fancy voltage BECs on a flight controller or PDB that makes life simple ...



Lol right?  I got 7v coming in off the NiMH main battery but I need a cleaned 5v for the video system and 12v for the crazy bright LEDs (cos ... nighttime driving of course).

So right now I have a basic but very capable surface FPV vehicle.  This thing is pretty boss and can rip.  But car RC is sooooo not the same as what we do here.  Some considerations ...

Surface Radios and ESCs are Specific to Cars

Surface pistol style radios work specifically for cars not just for the steering knob.  While pulling the trigger is like stepping on the gas, pushing it forward does not engage reverse.  The first forward push engages brakes lol.  The second forward push engages reverse.  Both brushed and brushless ESCs are programed to calibrate for this.  This presents a problem when considering the use of traditional stick radios which brings us to our next issues ... range.

Range Sucks

You get about 300 meters on standard 2.4 in practical driving conditions - meaning not in a wide open field.  This is still pretty fun.  You can drive out beyond LOS and start harassing bystanders with your squeeky standing still left-right steering lol.  But I would really like to be able to get way out there.

Obvious solution is 900mhz.  Problem is the issues of using stick radios I mentioned above.  So you gain great range but you lose on all the cool features specific to car RC that you can only physically get from a pistol style.  You may be able to program switches to accomplish braking (as you would for reverse) but not sure.  You may also be able to saddle a module onto a pistol style radio but that is even more experimental.  I plan to stick to 2.4 for now but slap a ghetto wifi signal booster between the radio and the antenna.

No BF OSD Here

I really wanted some form of OSD if even just the battery voltage (nevermind the batteries outlast my goggle lipo lol).  Still, something would be nice.  I had thought of using a cheap F4 flight controller to get OSD readings along with GPS telemetry but then issues of arming, etc ...  Just too much trouble for what it is worth.

Then I remembered back to the Naze32 days when OSD was just starting to be a thing.  So I hunted out the MinimOSD and found the Tarot GPS+OSD somewhere in China and hopefully that arrives sometime in my lifetime.  I'm not sure how the GPS works but it is something.  And the OSD can also provide some indication of battery voltage.

2 Channels?!  TWO!!

Don't ever complain you only got 8 channels cos of telemetry.  These dudes work with only two friggin channels.  I get that though - gas and steering.  What else do you need right?  Well, I'll tell you what I need.  I need to be able to turn my LEDs on and off.  I mean cmon, driving FPV at night is no joke!  I need to be able to turn my VTX on and off.  That shoots gets hot man!  And of course I need to be able to pan my camera left and right.  "Look both ways before crossing the street" ... it's for safety!!

So I am on the lookout for surface radios with more channels.  There seems to be a lot of Chinese knock off makers or lesser brand names that make very respected radios.  Also, I need a scroll knob for the pan servo.

Anyway that's where I'm at for now.  Not sure how long I'll stay interested because drones are definitely WAY more fun.  But when it's super crowded out and you just gotta get that FPV itch itched, this is not a bad way lol. 

I don't know how much money you are wanting to blow on this project, but there are surface radios with 3, 4, 5, 6 and 7 channels available. Very popular in the crawler world. And there is an FPV car thread on rctech.net if you are interested.

Honestly it's just a fun thing to mix things up a bit and see how far I can take it without having to involve antennas named "yaggi" or frequencies in the 400's lol.

So it's a little tough to make a cool car video because the scenery doesn't change all that much LOL. But here is what we got so far ...

A peak at the mods I had in mind schema'ed out as much for my own benefit as it is meant to help other weirdos wanting to do this lol ...



I don't think I really need the PDB but I'd rather use it in case I need to expand later. Also, I just hate spliced wires. Parts are trickling in now with the GPS coming in from China lol.

Did you see this? DJI Robomaster.

https://m.dji.com/product/robomaster-s1

This is a very cool project.

Damn you Ronin as you have made my mind tick over as I have an old rock crawler in the shed that wouldn't take much to get going lol

What makes this worse is tomorrow I have to drive to the train station and what is next door the the train station. A bloody hobby shop that specializes in RC Cars which has all the parts I will need to make it run again and it is pay day

I wonder how Crossfire would go

(25-Sep-2019, 04:46 AM)voodoo614 Wrote: Did you see this? DJI Robomaster.

https://m.dji.com/product/robomaster-s1

OH NOES!!!!

(25-Sep-2019, 04:51 AM)UrbanJungle1966 Wrote: I wonder how Crossfire would go

Dude, this is fun lol. But I also like to build as much as I like to fly/drive. So while this is literally a fraction of the fun of sUAV, I get a lot of satisfaction in building the thing too. I'll tell you what ... this all started with a $20 cheapie tank RC impulse buy that I slapped a spare BetaFPV cam on lol. So that trip to the place near the hobby store sure sounds like a sign to me! LOLLLL

Ok so I have not dabbled in RC cars long but from the research I've done, using 900MHz is problematic ...

While using traditional 2-stick radios are not that uncommon and what few LR car dudes (e.g., Henry the RC Car) I've seen use that, I don't want to sacrifice the cool features of a traditional surface radio namely the braking by pushing forward on the trigger and the sweet steering wheel. I have come across one passing reference to someone who managed to rig an XJT module to a pistol style radio, but zero information on how they did it.

At the end of the day, my sense is range has never been top of mind for these RC car dudes. And why should it be, their LOS races make DRL events look like a cub scout party. It's serious stuff! Anecdotally, what few "range test" videos I found were of some dude going, "yup that there gotta be 100 paces or so what ya gonna do drive with binoculars?? That's good range to me yessir!" LOLLLLL

For now, Im going to see what this Futaba 4PL can do with its R2104GF rx. I was getting pretty decent range with the Spektrum 2-channel that this thing came with so I'd expect even better. I'm also considering one of those wifi boosters.

Ok man so let me know when you get your crawler FPV'ed out LOL


[edit]

P.S. ... just a little somethin to tick your mind a little more. If your vehicle comes with a plastic driver dude, the Runcam Split Nano 3 fits inside the head like a pea in a pod LOL.

I have a dude 

Only bumma is plans changed for transport tomorrow so I wont be hitting the hobby shop and will have to wait until the weekend or next Thursday. Probably for the best as it really needs a clean and I should see if it still runs lol

   

LOLLLL it begins!! Yay I got someone to talk to now LOL.

Parts are starting to trickle in and using the dude's head to hold the camera is proving to be an issue. His head sits right over the top of the rear shock absorber with maybe 5mm to spare at best. I picked up some Hextrinik HXT500 micro servos but I'm going to look for even smaller. If I can't do a direct connection cos of the spacing, I'll have to come up with some pulley system.

Oh let me ask you a question about that on/off switch that comes out of the ESC of these things. Any way to tap into that switch so it also has control over other peripherals run off the same lipo?

If you are deadset on going 900mhz, I did find this R9 Mini to PWM converter: https://www.aliexpress.com/i/32920328845.html

And this 4-channel PWM converter for Crossfire: http://team-legit.com/TBS-Crossfire-Nano..._2227.html

One thing I have not looked into is UHF 400mhz. I think that would really be ideal.

Well start yer grinnin' and drop yer linen loll.

I found this micro servo and mocked up some 3d prints based on the specs. I think it might actually be possible to fit both this micro servo and a Runcam Split Nano 3 inside the dude's head LOLLL ...

You have a very nice project. I was wondering why not more of the RC car guys are not doing FPV. Your next goal should be the head tracking camera. I know it has been done. But it will still be very cool.

I did look into a headtracker but not only could I not find a module for sale, I would've had to go with my Frsky radio losing all the benefits I mentioned earlier. But if it turns out the range I'm getting just isn't enough, I may have to go that route for 900mhz.

You are way further ahead of me on looking into FPV RC Cars. My initial mission is to get the old girl cleaned up and hopefully running by the end of next week and take it from there. I know I will need to sort out the suspension as it has sagged badly but I still have a lot of spares so hopefully that wont be hard plus parts seem to be available.

My car is a vintage 1993 Tamiya Super Hornet. It's actually a classic Tamiya car which I find very amusing. It has a following and people are restoring them

Since I have had a sleep on this I have now resigned myself that this is going to be another one of my big as Ben Hur projects and with the technology now available the only limits are my imagination

With power I was thinking along the lines of putting in a power rail which can be tapped off to power up whatever is needed. Don't know the proper name for it but basically it is a metal strip encase in plastic with holes you can push wires in and screw them down.

My other thought was wouldn't it be cool to make a quad car. Think about it. Race along the road, flick a switch so the arms fold out then fly away. That would be cool. Also head tracking making the dudes head move instead of just the camera

That's a sick buggy. 1/10th scale is nice I'm guessing they don't flip over as much as 1/18th. Lol that's awesome it's got a cult following.

LOL I just want to get this guy road worthy first then I'll start thinking about making it fly and stuff. I made some progress with the FPV system. The Tarot OSD GPS works. No DJI accuracy here but anything's better than nothing. Also looks so tech geeky chic LOL.