Worlds FASTEST R/C Tracked Vehicle

this video is sponsored by factor in this video I set out to build the world's fastest RC tank or snow cat or whatever you want to call it the original RC test flight snow cat kit was pretty dang fast compared to any other tracked RC vehicle on the market but it was still pretty slow compared to what I built next which was a quad motor version that ran on 12s batteries or 50 volts I never measured its Max Speed but it was probably around 15 miles an hour or so which is pretty fast for an RC tracked vehicle it could have even been the fastest in the world at the time hard to say this time around I'm going to start the design from the ground up and ditch the gear driven drivetrain altogether electric skateboard Motors are remarkably powerful they have quite a bit of torque which means they can typically be used with a pretty small gear reduction or even just direct drive in the case of Hub Motors I figured if these motors can push me along this fast with a three to one gear reduction then they should be able to get an RC vehicle going super fast especially if it's direct to drive so that's what I'm gonna do I designed all the 3D printed and CNC routed parts for this build in onshape the frame is going to be most mostly made out of aluminum strips that I just cut and drill by hand so those aren't in the model but if you want any of these models they're available through onshape at the link in the description onshape is a browser-based CAD program which makes collaborating and sharing files super easy all my viewers have full access to all my cad designs all you have to do is create a free onshape account and boom there you go you can go download them or edit them or whatever you want to do I recently switched over to onshape and so far I love it I found it to be fairly similar to SolidWorks so it was easy for me to pick up a CNC cut the motor mount out of quarter inch aluminum plate on my stepcraft m1000 I had to screw the piece down to prevent it from moving while cutting the outer profile but once it was done it was time to mount them on the motors I'm using two of these 6374 140 KV Motors that should be able to do about 4.7 horsepower each I mounted those to the motor mounts with M4 screws I also stuck on an extra bearing in there for support to attach the 10 millimeter motor shaft to the 15 millimeter axle I'm using these big shaft couplers that just clamp on there these are the bearings for the drive axles I'm using two of them because they're kind of thin they'll be taking a lot of impact since this thing is not going to have any suspension I cut the axles down slid them into the coupler and then slid the shaft brace thing on over that these are printed in petg for some extra durability the motor mount was screwed onto the shaft brace with some M3 self-tapping screws all these parts are printed on my new Flash Forge guider 3 plus this is my first industrial grade 3D printer it uses a core XY design and can print at up to 250 millimeters per second the part that is printing here is the frame sidewall that will also hold the mid axles the guider 3 plus has a flexible bed so the parts just pop right off then it was onto the aluminum strips that 4 from the majority of the frame I cut those down to length on the miter saw and then marked out the hole positions with a little 3D printed stencil a center punch to the hole positions and then drilled them out all those bars get slotted into the 3D printed Parts on the frame and after a whole lot of screwing the bulk of the frame starts to take shape damn the sidewall sections then get screwed into the sides those add a lot of stiffness to the frame and prevent it from skewing then the wheel hubs clamp onto the shafts and the drive Wheels pull onto those I'm reusing some of the parts from the old snowcat and that's why they look kind of worn out next I started working on the electronics I'm using vesk 75 100 motor drivers for this build and they will need to be waterproofed so to do that I took them apart and started pouring epoxy everywhere I thought I had covered up all the connectors but didn't realize there were some little holes at the base of the USBC connectors that were open after spreading the epoxy all over the components I closed them back up screwed the cases back together and then topped them off with even more epoxy after the epoxy cured I uncovered all the connectors the base of the USBC connector had filled up with epoxy and this just barely prevented the connector from making contact I cut about a millimeter off the USB connector housing and thankfully that made it work close call next I cut a deck got a Plywood And bolted that onto the frame the motor drives also got bolted onto the deck and then I connected all the wiring to the motors after that I plugged in a battery and ran through the whole vest configuration process I got them set up for bi-directional rotation and to use a pwm signal for control this is a big motor protector that I printed on the guider 3 out of normal pla that attaches right onto the front of the vehicle and is screwed in place to protect the motors these are the front axle holders they can be swapped out with different ones to adjust to the track tension then the front axle goes in and the wheel on that the wheel is held in place with a little c-clip here's the mid axles going in and the mid roller wheels these are made out of TPU so they have a little bit of shock absorption ability I'm using an Omnibus F4 SD flight controller running RDO pilot Rover only really for the login capabilities so I can measure the max speed I waterproofed the flight controller with epoxy but was sure to put oil on the connectors and SD cards so that they wouldn't get glued in there the flight controller got screwed onto the frame with some standoffs and then I put the tracks on for a quick test this thing has like several horsepower oh this is the crazy fast version it should be I've never turned it on before oh wow this might be explosive this is the skateboard motor yeah this thing is so touchy oh my God this thing is terrifying after that I put the top deck on and then took it out to the field for the first outdoor test but first I need to eat because I'm hungry but I also want to go test the snow cat er I don't want to spend time cooking luckily I have a stockpile of factor meals in my fridge so I can just pop one in the microwave and boom two minutes later it's ready to enjoy quick and easy that's why I love Factor meals get factor and have delicious dietitian approved meals shipped straight to your door check out this cacio e Pepe Mmm delicious it was so good or how about this alfredo chicken breast with veggies also delicious this jalapeno cream all Burger was the bomb and the chorizo chili is definitely one of my favorites all you gotta do is choose your meals online and a couple short days later they show up this really is the easiest way to eat well with 34 Chef prepared weekly options there's always something new to try in addition to just meals they have an assortment of quick bites smoothies juices and more satisfying add-ons look and feel your best best in time for warmer weather with calorie smart meals around 550 calories or less stop wasting time and dealing with food the old-fashioned way head to factor75.com and use code RC test flight 50 to get 50 off your first Factor box while the steering is very touchy it's hard to control for the first few tests I'm using a 6S Lipa then later on I'll switch over to a 12s light boot the fact that this thing is direct drive means that there is no gear noise and it's also using field oriented control so the motors are silent this means the only noise it makes is from the tracks it sounds so much better than my previous snow cans [Music] this is where I learned that these tracks are not quite durable enough to handle a 25 pound vehicle cartwheeling along and smashing into the ground I broke a track link already additionally I discovered that there was a problem with the edges of the track links getting stuck under certain parts of the frame snapping off that's why it looks like it exploded right here we got Paul here from New Zealand what you got for us today Paul you know we got one of the old kin drone squirts good little piece of cat got some extra carbon braces on the bottom and this one's got some extra secret sauce it's got a little little Servo in there so we can control the picture of the camera as we fly sick we're gonna chase the snow cat [Music] [Music] [Music] [Music] [Applause] [Music] [Music] foreign [Music] on this day I was still only using a 6S lipo sick yeah feel the motors they're cold definitely broke some more of this plastic though I gotta try and get this all the snow off of it looking at the RDU pilot logs we can see that it hit a top speed of 11.95 meters per second or 27 miles per hour the motor guard got busted up pretty good probably because the edges of the track were catching on it so I decided to print a new one with this Splash forged carbon fiber petg this stuff is super durable and I also increased the wall thickness of the part and CAD so the old one got swapped out and the new one got swapped in then we were ready for another test this time I took it up to the mountains and the snow was very deep there was probably about two feet of fresh fluffy powder still using a 6S battery here it worked pretty well going in straight lines but it was difficult to control the turning in the deep snow this version is also a lot heavier than my previous snowcats so that doesn't help at all in deep snow can't even see the thing it's just in a bubble of snow oh one thing that you'll notice is that it rides pretty nose up this is because the motors are really heavy and they're in the rear of the vehicle it actually worked quite a bit better when I was driving backwards so the motors were in the front but this was kind of difficult to do because I made the steering be reversed I could have just swapped the motor outputs and driven in reverse all the time but never got around to it it's driving backwards during some of these shots but not all of them it just stops and then it like tips back and just dig straight down wow foreign [Music] foreign next it was finally time to try a 12s battery these are two 2.2 amp hour 6s packs in series to make 12s so this is going to be the first test with 12s for this thing oh that's really heavy I'm not actually sure that it'll be any faster because there's a thing called erpm limit in the vesque motor Drive software that limits the electrical pulse speed sent to the motor so if the erpm limit is set too low for 12s then it might be the same speed I'm not sure let's find out it seemed a bit faster than before but not by that much so this made me think there must be something going on in the best code that's limiting the RPM if these were normal bldc escs doubling the voltage would roughly double the speed but that's clearly not the case here another thing that could have been limiting it is the battery's C rating they were rated for 120 C but they also had Fairly thin wires and just little xt60 connectors so maybe that was a bottleneck oh oh that doesn't quite look right look at this there's bits and pieces all over the place here there's so much tension on these tracks right now it's Gotta slowly work it back over there we go oh nice but look at that got a big old Gap in the middle now let's see if it still goes okay so I'm gonna take it home and check the erpm limit on these motor drives and see if I can get it to go any faster so on this day we hit 12.57 meters per second or 28 miles per hour I found that the erpm limit was set to its default of 10 000. setting it to 35 000 to seem to remove any RPM limiting setting it any higher it would just make the motor RPM max out prematurely sure enough the erpm limit was a big factor [Applause] oh that was crazy on this day we hit 19.17 meters per second or 43 miles per hour I brought it out again the next day and hit a similar top speed hmm [Applause] in order to try and squeeze as much speed out of this thing as possible I trimmed the tracks down so that they were much more narrow this should reduce air resistance quite a bit since the top of the track is moving forward at Double the vehicle's forward speed so if it's going 43 miles an hour the top of the track is experiencing 86 miles per hour of air resistance I also got two additional batteries so that there are two in parallel and two in series that should help with the current draw after that it was back out to the field okay it works this thing has enough power to pull into a wheelie while it's already going over 40 miles an hour it's a good thing I can also drive upside down [Music] [Applause] [Music] on this day it hit a top speed of 22.24 meters per second or 50 miles per hour I'm pretty sure that's the current world record for a tracked RC vehicle after that I put the wider tracks back on and Sebastian and I took it up to the snow to have some fun the direct drive snow cat weighs a lot so Sebastian's just gonna tow it to our driving destination way to go Sebastian make like a horse unfortunately this area was pretty wind scoured so that made the snow quite icy this made it really difficult to build up speed and stay going in a straight line I should have installed the little metal spikes into the tracks for this one but it was still pretty fun to play with them so Jesus whoa foreign [Applause] I hit a stump sticking out of the snow and that messed it up pretty bad thank you after that I fixed it back up and took it to the opposite environment the beach I also put the trimmed down tracks back on since they were already super worn out I knew the sand was going to wear them out even more wow we seized motor already the main problem was that the sand was getting jammed in between the motor belt and the motor guard can we get a full throttle well my remote even has sand in it sand was also getting into the motors themselves which was pretty nasty oh it's bad man it sounds so bad sand was just getting stuck in between this red cover and the motors oh yeah look at that that's gnarly but after taking the motor guard off it did work decently well thank you ouch at one point the motor Drive started glitching out and it decided to dig itself a nest so after a quick power cycle it was back up and running foreign got everywhere and chewed up everything luckily the motors still work but that's a wrap for this project I never got around to measuring how much power this thing was pulling while driving at Full Throttle but based on this calculator that uses RPM and phase current it's safe to assume we were doing about 2.36 kilowatts each or 4720 Watts total that's 6.32 horsepower I'll put a link to this calculator in the video description if anyone wants to look at it here are some pictures from customers that bought and built the snow cat kit big thanks to everyone who donated towards the mold cost and bought the kit in total we produced over 43 000 track links so that's pretty cool each snow Cat uses 104 links so that's 413 Vehicles worth of track links it's so cool to see people driving around their own snow cats and especially to see the modifications that people have done there's some pretty awesome ones out there if you're watching this video and want to buy a kit you're probably too late because I'm not doing another batch but at the time I'm saying this there are a small handful of plank cat kits still available there will be a link in the description to that so that's it for this video thanks for watching bye

Channel: rctestflight

Views: 1,722,649

Keywords: rc, model, snowcat, brushless, direct drive, fastest, fast, world record, worlds fastest, tank, tracked, tracks

Id: W5nBqzW9lXY

Length: 19min 41sec (1181 seconds)

Published: Mon Mar 20 2023