In this video I take on building the
world's largest rideable hexapod, Megahex. A passion project of mine that has taken up
the past year and a half of my life. What started out as a simple three-month build
turned into a year and a half of failures, breakdowns, and rewrites. So close. And I think we have to cut
our losses with this project. We even made three entirely different
videos before scrapping them in favour of this video that
you are watching right now. Do I ever have a story for you. It all started when I came across a
video of a Princess Auto excavator which was capable of orienting
itself by using the bucket to stand up and maneuver. So what stops more legs lifting
more bodies, as one giant unit? As I was working on Power Loader and
other hydraulic projects I was like this is doable like we could do this. All right guys, the plan is simple. Weld together six excavators, wire all
the engines and then program the legs. I think we can do it in three months. The first month went great. We partnered with Princess Auto for this project. They provided us with six excavators
and an in-store spending budget. Without them this project wouldn't be possible. When I first envisioned this thing
it was just gonna be a rectangle. Like the plan was literally cut the
frames, shove some box tube through it, throw a few welds on it. Each leg could just do the exact same motion, the only difference is what
time that motion happens at. But then the frame was way too large
it wouldn't fit through the door, the legs were way too close to each other which
made the frame even bigger and even less stable so we were like okay we have
to make this a hexagonal frame. And that just brought so many extra complexities. The joints and all the angles
had to be super precise, the motion of the legs was no longer going
to be the same between every single leg. Every leg had to have a specific motion profile and that just instantly it was like
okay we're in way over our heads. In SolidWorks everything lines up perfectly. You get to the real world and honestly
I should have expected this... Started chopping these frames apart we shoved in
the box tube and then we started laying it out and we're like what is going on? Like one side is longer than
the other and we're like none of these legs are where
they're supposed to be. Obviously, they're mass manufactured. So like we should have known this. If the frame is going to be that far out then like the motion of each leg is
gonna be completely different and our stress analysis that we did in
SolidWorks just not going to match up. Like something is going to break. That required us to start chopping the frames apart that we're you know
supposed to be used for alignment we're now being completely cut off and re-welded and we basically had to
tolerance the frames ourselves. We had to make jigs we had to make like brackets
and it went from like a two-day welding job to over a week of just like trying to
get this thing perfectly squared up. Once we were ready to start attaching the legs
I was kind of feeling defeated at that point I was like if I've had this many problems
already this thing is going to be a nightmare. We started attaching the legs and
things were actually going pretty well. Each leg was attaching properly,
the spacing was all correct everything was moving smoothly. It was looking epic and I was starting
to see what this thing could become. I knew this thing was going to be large but
actually seeing it in person this thing is huge! Like this is going really
well, we're making progress, we're gonna get to the test relatively soon. A lot of anticipation. A lot of like please work please work
like there's so much riding on this. I had you know a lot of doubts I
was like what if the welds crack? You know, what if the frame is slightly
twisted or we have a hose pop off and this whole thing just
comes crashing to the ground. Honestly I told everyone this and I was surprised that anyone even volunteered
to step foot onto this thing. Holy crap! All this work is finally paying off. So we need some computerized control
to be able to make this thing stable because right now it's a little hard
to drive with four individual pilots. Well we know the system can lift its weight. Let's take a minute to talk about hexapod feet. As you can tell I've replaced the bucket on this
leg with a brand new design of a hexapod foot. The buckets, well they're great for digging but unfortunately they don't
have great surface contact. With a new design we have lots of ground contact have more motion with this
cylinder, and it looks way cooler. Ideally we'd like to be able to drive
the entire thing with just one pilot. To do this we need a computerized control system. The whole control system starts
right here at the Linux computer. It's responsible for calculating how to move
each individual leg based on the user's input. That data is then sent over
to our Kunbus Revolution Pi. It's responsible for taking data in and figuring
out how to move the legs to the right position. It does this by first calculating the position of each individual joint based
on the row potentiometer. It then compares that value
to where each leg needs to be. It then sends signals to our servos to
move the valves to their desired positions. Unfortunately the Kunbus system does not
really speak the same language as the servos. It outputs 24 volt signals and
the servos require 5 volt inputs so we've created a PCB using Altium
designer and got it manufactured by JLC PCB to act as a translator between
the Kunbus system and our servos. By the way you can try Altium for free and
get 25% off your purchase with my link below. Ben jumped into to this project and began
working on the control system and software. As you would imagine there's a lot of code. In order to test this without needing to use
the actual Megahex, I'm using simulation. This simulation takes the CAD data
from SolidWorks and hexapod math combines it into one to give us
an accurate visual of the Megahex. We were feeling confident,
perhaps a little too confident, as we were about to enter integration hell. The design of this project is critical and just
like our other projects, we use SolidWorks. SolidWorks is our favourite
sponsor because it is super powerful design software which empowers us to refine our ideas into manufacturable
designs and build crazy things like Megahex. For the first time ever SolidWorks
is available to you guys as the 3D Experience SolidWorks for Makers offer. This is actually a huge deal because SolidWorks
is one of those industry-leading softwares that was normally only available to big companies. But with the Makers offer anyone can get access at a super affordable price of only
$99 per year or $9.99 per month. Plus we have negotiated to get our viewers
an extra 20% off if you use my link. This is like getting SolidWorks for 99% off! Which is unheard of in our industry. You can get the world's best design tools and turn your ideas into reality or
browse the gallery of online models. Join the global community of creative makers today
and use my link to get 20% off your subscription. Big thanks to SolidWorks for sponsoring
this video, now let's get Megahex walking! After countless hours of troubleshooting we finally have all the hardware
and software integrated together for the first test of a Megahex leg. As you see behind me is the
simulation of Megahex walking. The black leg is the real-time
position of this foot and the transparent legs are where Megahex wants to move. So if you can see me moving these
potentiometers, updates the real-time position. So theoretically once we get this engine started up the Mega hex leg should move into
the same position as the simulation. And once we give it a command to walk hopefully
we'll have Megahex take its first steps. Starting up in three, two... Well it didn't explode and catch
on fire so that's a good start. It looks like it was trying to move and
that's what the simulation was telling us. I just don't think it was trying hard enough. We have a bit of tuning to do on the joints and
we'll see if we can make it a little bit better. I think we need to slow down the simulation. So hopefully it has a better chance of keeping up. I'm trying to figure out what I actually need
to do to slow it down the way we were thinking. Add another 50% to the PID values? Yeah. Still not responsive enough. Not on the tibia tarsus or femur.. Turn them up? I think the femur is what
we need more of right now. I trippled the leg lift
height..that's a lot better, yep. Okay double the femur? Heck just go like three times more. That's walking! So what we're doing is we're turning up
all the gains so it's gonna try about twice as hard as it did
last time to try to keep up. The concern with this is if we go too high
the leg will basically rip itself apart because they'll start oscillating. As it sees an error it'll try to
overcompensate for it and basically overshoot and that gets worse and worse and worse. Up until the leg is basically going
full speed forward, full speed back, full speed forward, full speed back and doing nothing of what
we're trying to get it to do. Hey Bogdan I think I see an issue over here. So the reason we have all of these
plots and simulations everything set up is so we can diagnose weird issues like this. We tried looking through the code trying to figure out like what do we change you know we
revert back to the old code we run it still having the same issue
we're like what is going on? Like why is this one joint just not moving at all? So all three of these joints seem to be
tracking fairly well except for the femur, I think there might be an issue with the servo. Oh the freaking servo. Oh yeah these are toasty. That one on the bottom especially.
You have the thermal gun? In the middle, oh yeah that thing
is over 100 degrees Celsius. See the other ones comparatively are
like 60 which is still not great. These windings are supposed to
be this bright orange colour, that black coil states that this motor is toast. Replacing a single servo
would take like three hours, like oh great another servo
failed...well there goes another week. We obviously know we have to replace all the
servos and we have to figure out a solution which ended up being changing different springs. When the bigger spring was installed every time the servo moves it has to
work on compressing the spring. With the smaller spring the servo
is not going to be working nearly as hard therefore generating less heat. The second thing I did was I added
this computer fan to keep some fresh air moving across the servos to keep
them all just a little bit cooler. And with different springs all
of the tuning we've done that week was just out the door. Completely useless. And that was just like a huge hit to our progress. With testing this whole thing I was starting up
that engine stopping at every like 10 minutes. So we're like right we need new engines that have a remote start but also were
a little bit more powerful which meant we can use bigger pumps and get a lot more flow hopefully increasing our
speed and power on all the joints. So we spent like two weeks just like pulling all the old engines off pulling all the old
pumps off undoing all of our hydraulics. Luckily mostly everything was you know drop-in
replacements but it was still a lot of work to rewire all the engine starters together. We wire all the stops together, we had
to add that to our emergency stop system so it would actually shut all the
engines off and that was a lot of work. The exhaust, honestly we could have
probably gotten away without it but even just having one engine running and trying to like get a vent over top
of it while we were testing was just really annoying. And I was like there's six of these
things not only is it gonna be crazy loud like right around me but
also it just smelled terrible and I was really worried about my health or
anyone else who was gonna be near this thing. I got Mike to actually take
some time and plumb in some proper exhausts as well as some proper
baffles, quiet the whole thing down. And you know exhausted out the back
so it's not blowing into my face. This point was like five months, in like
two months over the estimated timeline we still have not seen a
single proper stand-up test. With all the new engines and the the
new pumps that we had to get and the replacement servos that you know didn't burn out the new springs, the budget.. We spent the entire sponsorship budget
in the first like three months and now we're just like this is coming out of our pockets. This was the day.. actually not the first day. We tried it the first day and then
some of our engines weren't firing up. We tried the second day we're
getting hydraulic leaks. Try the third day some of our
senses were misreading values. So we're gonna fire up all six engines
and see if the platform rises to the air. This is without people on it,
fully computerized controlled. so we should be able to just hit a
single button and the whole thing should rise more or less evenly off the ground. Safely right? As long as there's
no one near it should be OK. Firing up! I'm trying to stand this whole thing
up and at first it's like going well and this whole thing like five feet in the
air starts curling up like a dying spider. Me and Ben are just like looking at each
other being like are you doing this? I don't have the controller I'm not doing this. And so like I slam on the
e-stop and we're both like confused as hell we're like how do we fix that? It could have been any number of things. It could have been hydraulic issues, it could have been software issues,
it could have been electrical issues it could have just been you know mechanical
issues with the valve getting stuck or something. Luckily we look over all the data and it
turned out just to be a simple code change. Our leg was actually trying to go past its limit. Two lines of code, upload
it again, ran the system. Restarting. And this thing just perfectly rises into the air. All the legs on the ground. It was a sight to behold. Now the legs lifted up and moved around so
we're like okay we're on the right track, we need to figure out how
to get this thing outside because there was no room in the shop to test it. We spent the last eight months
or something working on this and now we're just dragging
it out of the concrete. We were obviously optimistic because
the simulations were working. Starting robots. And like this thing just like
barely lifted its foot up just like drags it across the ground and just like slowly stumbles over just like dropping the
weight onto every single leg. Once there's a lot of load on
them they're not really moving. It brings the leg over but
it doesn't actually have that much force to actually push its own body forward but overall it's not on fire and we
didn't break anything I don't think so, good first test. And we're looking at this data we're looking at this thing walk. We changed a lot of tuning values, we
changed the way it's going to try to walk. And every test following that
we'd spend a day dragging this thing out it would like stand up take two steps, one leg would fumble, the position would be off,
the whole thing was just tip damage something. It was just so frustrating.. It was really upsetting just to see this
thing slowly damage itself more and more. Yeah Bogdan we left some paint behind. Wore it all the way. We just lost our alternator. Do we have enough fluid in the reservoir? Why are we having issues all of a sudden? Should I just bump the starting
threshold up a little bit? The issue of it dropping as it's
taking steps has gotten a lot worse. That sensor is gone. Yeah, I don't think it's going. I haven't changed anything. One more try? Why are the servos...their
legs aren't moving up now. We've killed the starter on this motor right here. It's out of regular interval. Oh yeah we [ __ ] that wheel off. Break them in half a second we're so [ __ ] close. Everything is set up right now to work and now with the engines are being problematic. It's ready. It's good to go. We've got everything.. it's tuned. Six legs that were working. The efficiency of the testing it's not like oh make a simple code change run it again
make a simple code change run it again. No like if something goes wrong if one sensor
fails, spend a week fixing it drag it back out. Right now our femur which is our main
lifting cylinder doesn't have enough power when we're lifting three legs at a time. So what's happening is when we're giving
flow to other cylinders it's slowly dropping so after two or three steps the actual frame which was four or five feet above the ground
is now basically touching the ground. So we want to make sure that when it's
taking steps it's got enough pressure and it's got enough flow to sustain that height. Daryl take a look at this data. All right all right um if you want to zoom in or whatever take a look. Okay based off of that right there.. yeah
um.. just gonna need a little bit more work. Right there.. yeah awesome. I think I think I know exactly what he means.. Should be done in a couple days. Maybe the femur needs more work.. that's
it, needs more displacement over time. That's what I was going to say.. Femur..100% oh we just need to double ..Double it. So whatever the screw is set to and
the pressure thing just double it. It's called the pressure relief. If we just turn it a little bit
should make Megahex walk better. Still not perfect but it
is definitely a lot better. When we were seeing it walk backwards the body
was not dropping nearly as much as it used to and we didn't blow off any hydraulic
lines which is really good too. So..I kind of want to ride it. I don't think this thing will kill me. Worst case scenario just mild injuries. That first rise up off the ground, like when you're all the way up
high it feels really satisfying. when it starts dropping off it it really loses a lot but honestly
the ride is smoother than I expected. We need to max out all the
motions I think we need to increase that step over distance definitely yep. Because when it's loaded it's not moving
very much and it's slipping a lot. If we can get the legs off the ground
for sure it'll walk so much better. So let's bring it back inside for now. Lucky for us Princess Auto sold
other sizes of hydraulic cylinders which were almost perfect drop in replacements. We decided to try smaller cylinders on the
tibia and larger cylinders on the femur. We made the cylinder bigger because this joint was
lifting a majority of the weight of the Megahex and it wasn't quite standing up
with a slightly smaller cylinder. My grandfather. Six months ago. I'm not kidding. Hey Daryl, you know how many days I
wanted to punch you in the face XD. Cool..we sprung a leak. We killed the cylinder. Well that answered that question very quickly. Covered the whole thing in
hydraulic fluid..oh my laptop. After a spectacular cylinder explosion on
the tibia we had to change those ones back, but the femur cylinders.. they worked! Get back out there the next day try it out again. Every test that we ran it was
walking just a little bit better just a little bit better just a little bit better and like the only thing that kept us going was
that we were seeing consistent improvements. We could see we're like oh maybe if
we just change this one more thing like next test is gonna work, next test
is gonna work, next test is gonna work. And we're like months into testing making marginal improvements but it was
it was almost there almost there. We've upgraded our feed lines from
the pumps to make sure we can get the full flow that the pumps can
provide without a loss in pressure. We changed over the step over
distance so how far it's moving. We changed how fast it's moving. There's a lot of changes so we're
expecting this not to work but it kind of give us a better idea of
what changes have what effect. Finally we get this thing powered up at this point we have like no hope. We're like all right one more
test let's just go for it. And it took one step. And it took the next step. And it took the next step. Three steps in a row like this is a
good start like keep going keep going.. and it just kept going and going. The platform was staying above the ground. Nothing was failing like all the
sensors were reading properly and just like one step after
the next and there was there was mud all over the ground and it
was just like splashing in the mud. Like, yes! Like this thing just walked across the
entire parking lot we were so excited. Turn this thing around bring it back around. And this thing starts turning around and
we lose communication with the controller and the thing just like steps on our trailer. And we're like uhhh. I'm willing to bed that..we lost
communications with the controller. One of our wires ended up coming unplugged but
like we knew that like okay this thing is working. We had a couple of YouTuber friends
come over I think it was Jake Laser, Nigel from Nile Red, and Allen Pan I think. As long as we keep the fatalities to
under three we're doing pretty good. Driving around the power loader having fun. I looked at Ben and I'm like do you
want to drag this thing outside? And like get to show it off to them? Power this thing up and just just like the
last test we just gave her the forward command. I think they were blown away. Dude!! Here we goooo! The following week later we just got to work and
there was just fog across the entire facility. Dragged it all the way out
to our field, super cool. Walked around the dirt you know threw up some
of our lawn, the Power Loader in the corner. Stepped on the pumpkin, the fog in the background. And then I'm walking I'm turning I'm turning and
then it's out of nowhere like the side dropped. What's going on? Get ready to hit the e-stop and look over and the
leg is like completely not attached to Megahex. I could not believe my eyes. The thing is.. these excavators.. we were
pushing these things way past the limit. I'm surprised it didn't fail
earlier to be completely honest. But yeah the excavator frame just
completely tore itself in half. This is why companies go
bankrupt when they build mechs. I'd probably have a better return on investment
making a video where we dig a big hole, put a bunch of cash inside and light it on fire. Brought it back in the shop,
got the whole thing welded. Next day we take it back outside
ready to do another test. And same leg, different spot
crash into the ground again. I go over to look and the frame
is just twisted and torn in half. This was a main part of the frame. This one's going to require chopping
the frame again realigning everything new bushings, new body tubes, welding
all around, new gusset supports. This was probably another two weeks to fix
and like I looked at this and I'm like.. All right well for better or for
worse like we're done filming Megahex. Frame that the leg is connected
to it is now just ripped in half. If a single wire corroding a single connection
going bad could take days to diagnose. And I think we have to cut our losses with
this project because at this point it's it's doing us no returns. There is no way that we could keep just allocating
so much time and so much money to this project just to have it you know take five
steps and another thing breaks. You know we got our goal, it was walking, that was our goal. We reached it and
honestly it was time to call it a day. You know what without the support of you
guys and making continuous videos there was no way that this is going to be sustainable. Like this project was so much time, so much
effort, so many different learning opportunities. But really like completely honesty with you we
really should not have green lit this project. This project should not have happened. It was way more complicated than we anticipated, we had way more issues than we thought. The the timing and the difficulty
was just way underestimated and literally the only thing that
kept us going, was you guys. Every one of these failures was content. It was going to teach us something,
it was going to teach you something. And we really hope that
that comes across on video. This project is the reason we haven't been
able to post as often as we normally would and to make sure we show this journey in the best way possible we initially
edited a three-part video series but we felt like it didn't tell the whole story. We do think there's a lot of interesting detail in those videos and so we've made each of
those videos available to our members. I do not know if we're gonna ever be able
to do another project like this again. If you'd like to see us try
something like this again and hopefully do so without coming near bankruptcy, please please just subscribe like this video share it to anyone
else who you think would be interested and consider becoming a member. Because this was really expensive
not just in terms of parts costs, but the amount of labour that went into this, all the engineering time all the after work hours, we could not have done it
without support of our members. So thank you so much for watching this video,
thank you so much for your support and hopefully we'll see you guys back here with some
other cool projects in the near future.
make you wonder how much money and resources San Magnolia put in to designing the Juggernauts...
Fellow Hacksmith Watchers🗿
Check mate Boston dynamics
When do we mount the 57mm gun?
Sweet Christ. So it begins. I’ll see you guys in the 86th Sector
So it begins
they have about 120 years to figure out the rest so we're making great progress.
"still just an aluminum coffin" - Shinei Nouzen
yes it is