[Calaban]

ok 2 hobbies.. both of them very expensive (good thing there no girlfreinds hooks in my wallet... I guess.....)
- Warhammer 40k.... expanding Tau and building new SM armies
- RC Airplanes.... getting into the whole 3D thing

well, apparently, RC airplane stuff got REALLY cheap. I can remember when a servo gots $50, and a radio transmitter cost over $400.... not anymore! today, servos (micro minis even) are $10, and a radio kit (Trans, reciev, 4 servos) costs $120..... see where I'm going with this??

so, in my time learning how to keep the planes out of the ground, I've stripped out a few servos in my teething years. and now have quite a few servos and gears and such lying around.... and Ive got a few 'glitchy' recievers around now as well. >
the servos are teeny (smaller than half a box of matches), and the reciever is the size of a box of matches.. all of which can fit in a Rhinos cargo bay (incuding a 9v battery).

so what? well, I plan on putting a servo dead center of the predator interior, with z-bar linkages going to the turret, and side sponsons. the sponson Z-bars will have slips in them, meaning that they only grab the sponson when the servo rotation suits that sides movement (meaning I wont drive the sponson into the body), the turret will have a direct link 8) rotating turret, with a 'linked' effect to the sponsons (as the turred rotates, whatever side sponson will track with it.)

thats the beginner stage. maybe I can up-kit later models. the kewl thing is, I can eventually set up to 4 tanks with their own servo, and run them off of the same transmitter (4 channels), and if i REALLY go insane, I could go up to 16 tanks under one radio (4 programmable presets in my good radio)

I just have a couple of hangups at the moment, which I plan to tinker with tomorrow: Servos only have a 90 degree arc, and are 'spring loaded' back to center when I let go of the stick. theres a rheostat in each servo that controls this, maybe theres a way to bypass that, clip away the internal stops, and have it rotate 360, and stop when I let go of the sticks..... while a fully 360 servo wouldnt work very well with linkages, it WOULD work well as a drive motor for the tank itsself! (each servo has stronger than your fingers torque)


anyways, wild imaginings at the moment. re engineering stripped out servos for the motors and gears to make something actually workable is the hangup, guess I'll just start with the headlights and stuff first! (maybe put a SP400 (750 watt) motor on a Ork JetKopta! heehee naaw, maybe just a teeny CD player brushless motor.. I guess there IS such a thing as TOO orky!)

[akthomas89]

This is definitely one of the coolest things I have heard of. How cool would it be to have a remote control land raider?? Or an IG armoured company that is fully radio controlled! If you can even pull off the rotating turret with tracking sponsons that will be insanely cool.

You sir, kick ass. Good luck!

[mace]

Heh, I've always wanted to do this, but it's a bit hard with Tau tanks.. I'll probably settle for a headlight mod or something one day..

Regarding Servo's turning 90 degrees, you can modify them (take them apart, chop up the limiting gear thing - I think) to be able to rotate 360 - very good as a drive motor!

As for the other technical bits, I'm not too sure..

I'd like to make a full RC tank one day.. complete with lighting + sound..

[Calaban]

Ive already looked into the servos (literally!), and its more complicated than that.

see, theres a rheostat in there that senses where the servo arm is on a constant basis, and compares that reading with the input signal from the transmitters 'stick'. the way I understand it is the rheostat is a balancing act: when the radio signal input changes to a new 'variable', the rheostat kicks in... if the reading right now is too low, drive, left, if too high, drive right... until things are balanced again. pretty simple, but the problem is its doing this like 1000 times a second, and as soon as you let go of the (spring loaded) control stick, it all goes back to 0.

while there are internal stops inside, removing them wont do anything, because the stop is virtual, and is limited by the radio control sticks range of movement, and also limited by the range possible with the rheostat (since a full circle will make the reistance go to negative suddenly). this is a real stumper for me, and I may just have to goto the RC store and see if they have and 360 servos I can just BUY.

but yea, Im really stoked about how CHEAP all this stuff has become! oh, and TEENY! did you know there are 4 channel radio recievers out there 1/4 the size of a penny? and magnetic servos the size of an eraserhead? they make micro RC planes that weigh in under 10 grams.. fully controlled.. AND they sell PARTS for these! these are too small/weak for what I want to do, but the flight control servos are perfect, tiny and strong!

[SqurielLord]

people better keep thier mouths shut then. would'nt want to swallow a mini-rc plane!

mototize a crisis suit...mmmm.....

[Calaban]

progress!!!

Ive recieved a post on how to make the servos do what I want them to do (namely, add 2 equal resistors in place of the potentiometer), and have mounted a servo to a razorback turret, with full 360 degrees! super kewl seeing twin linked lascannons pivoting around remotely... with absolutely no wires or controls apparent! ;D I'm keeping the servos and mounting systems removeable until I get things locked down

so thats stage 1 of this project. stage 2 will be adding a drive servo to roll the tank foreward... stage 3 may be to make the drive a double servo setup so I can pivot the tank tank-style, and drive foreward as well. stage 4 would then be to add lights (headlights and a mini maglight searchlight). final stage 5 would be.... making all that stuff cram into a rhino chassis :P

I could post pix of stage 1, but really I need to video it to get full effect... and dunno how to do that.

[SqurielLord]

just take a bunch (rapid-fire!) of pictures and we'll piece it together.

[akthomas89]

How old is your camera? Most relatively new cameras (and a good deal of older ones) have some form of video mode, although often it is poor quality and 15 frames per second - either way if your camera does have some sort of basic video mode it should be able to give us an idea of how the tank looks and works!

If you don't have a camera like that maybe one of your buds does? Or a digital camcorder you could borrow?

I'm very interested to see!

[Calaban]

well, sure I can make a video, but I have no idea how to post it. photobucket is all I'm familiar with. give me some tips, and I'll give a video.*

[Calaban]

[update] I was so stoked about this project that Ive hurried up and completely built the servoed Razorback, and took step by step pix, with the intent of posting it here (and any other website that is more space mariney... too bad Bolter&Chainsword is dead and gone..* :-\ *ahem* Long Live TauOnline!!!!). and now its all finished!!! stand by for another thread in this forum called "servo'd Razorback" coming up as soon as I can type it!

I took a video of the razorback in motion, too...* but still am waiting for a how-to on how to post a movie* (its a 2.95M mpeg file, FYI)