Iron Man Helmet motorized hinge problems [video]

jayjayn

Well-Known Member
This is my first thread and have been following therpf for about two months and started my IM suit right away, im very appreciative to be getting so much info from this forum and now i need some help.

Well i've been having issues trying to get my hinge to work properly due to the amount of throw required to pull brake cables and how much it needs to go back to close the helmet.

I'm using a great detailed helmet from mightyjohn and he made me hinges for the setup here is a video of what im trying to get to work.

IRON MAN HELMET EYES LIGHT UP AND MOTORIZED HINGE TEST - YouTube

and this is mightyjohns hinges at work but only being pulled by hand

Ironman Helmet Hinge demo - YouTube


I got some help from Zabana and he suggested originally using two

HexTronik HX12K Standard Metal Gear Servo 55g / 10kg / .16sec

since he was successful utilizing it on his own hinge setup, but after constantly changing angles of the cables and lengths i realized that the servo's wasn't able to pull enough cable to pull the faceplate open.

I was thinking of either getting a longer servo arm and trying that way, but that would be a issue of trying to get that to fit somewhere inside the iron man suit, another thought was utilizing mini linear actuators but they don't seem fast enough and are twice or even more the amount that normal servo's cost.

I was trying to figure out how to modify my servo's for 360 throw but even with that i find there will be issue on trying to have it rotate back without crimping or even trying to put that sort of setup hidden in the suit.

I'm in need of help on what i should do to get the hinges to open up fully and have the whole setup fit somewhere in my suit, anyone with suggestions?
 

aron42486

Well-Known Member
I've seen servo arms that look like small pulleys, you might be able to use one like a mini winch. Getting your cable to follow a wheel's circumference might give you a little more pull.

Are you starting with your servo all the way over to one side and using the full range of motion?

Other ideas are to connect your cables closer to the pivot point on the hinge. This reduces the distance you have to pull but requires more force so just make sure your servo is beefy enough to handle it.

Edit:: I just watched your video and you are only using 90 degrees of rotation. Instead of going from one side to the middle "rest" position, go from one side full to the other. This should give you a little less than 180 degrees of rotation and add an extra inch or so of pull.

BTW, I also have a Pololu micro-controller, even though I haven't gotten that far along with my helmet yet. Interested in sharing code?
 
Last edited:

MightyJohn

Active Member
Love the paint job!

I've seen servo arms that look like small pulleys, you might be able to use one like a mini winch. Getting your cable to follow a wheel's circumference might give you a little more pull.

Are you starting with your servo all the way over to one side and using the full range of motion?

Other ideas are to connect your cables closer to the pivot point on the hinge. This reduces the distance you have to pull but requires more force so just make sure your servo is beefy enough to handle it.
I haven't gotten into the servo side yet, but those sound like good ideas.

Maybe a continuos rotation servo, but I can see where the fear for crimping comes in. Maybe a continous rotation servo with rack and pinion to make the cable stay linear?

Idea...
Maybe you could break up the main hinge into two parts (seperating the pull arm) and add a gear reduction connection. You would have to add another pivot for this and the cable pull will be reversed, but it could work. It will use more torque to pull thou.

Like one of those baby toys that you slowly push the top button down and the cylinder inside spins like crazy.

Here is a diagram of my thought on this (generic drawing for design protection, but it gets the point across).


jayjayn,
I have an idea on how to get those hinges of yours fixed, too. I'll send a PM.
 

aron42486

Well-Known Member
Love the paint job!



I haven't gotten into the servo side yet, but those sound like good ideas.

Maybe a continuos rotation servo, but I can see where the fear for crimping comes in. Maybe a continous rotation servo with rack and pinion to make the cable stay linear?

Idea...
Maybe you could break up the main hinge into two parts (seperating the pull arm) and add a gear reduction connection. You would have to add another pivot for this and the cable pull will be reversed, but it could work. It will use more torque to pull thou.

Like one of those baby toys that you slowly push the top button down and the cylinder inside spins like crazy.

Here is a diagram of my thought on this (generic drawing for design protection, but it gets the point across).

jayjayn,
I have an idea on how to get those hinges of yours fixed, too. I'll send a PM.
Might work, but seems like it would be more complex to make. Is sintra strong enough to make a gear out of? I'd be worried about the teeth wearing out.

Also, they would need to be thick enough to prevent them from slipping out of alignment.

Your system works MightyJohn, he might just need to make some minor adjustments to get the same result as you.
 

rockeagle2001

Well-Known Member
hmmmm...ive been thinking, are servos the only and easiest option if we want want to motorize an iron man helmet hinge? surely there must be something else that works like it or something similar.
 

aron42486

Well-Known Member
The reason most people use servos is because they are compact and very precise. There are a number of things that can move it up and down but getting the precision on where to stop can be difficult.

With servos, once programmed and setup properly its as easy as pushing a button or throwing a switch.
 

jayjayn

Well-Known Member
I've seen servo arms that look like small pulleys, you might be able to use one like a mini winch. Getting your cable to follow a wheel's circumference might give you a little more pull.

Are you starting with your servo all the way over to one side and using the full range of motion?

Other ideas are to connect your cables closer to the pivot point on the hinge. This reduces the distance you have to pull but requires more force so just make sure your servo is beefy enough to handle it.

Edit:: I just watched your video and you are only using 90 degrees of rotation. Instead of going from one side to the middle "rest" position, go from one side full to the other. This should give you a little less than 180 degrees of rotation and add an extra inch or so of pull.

BTW, I also have a Pololu micro-controller, even though I haven't gotten that far along with my helmet yet. Interested in sharing code?
unfortunately that's the maximum travel that particular servo can do, i ended up buying a arduino thinking my pololu wasn't working right due to zabana saying that the servo can do 180 degrees and later finding out it really doesnt =\ .. but it does do more then 90 degrees more like 110 i believe, but even if it did more im still thinking the cable will crimp since even at these degrees it already is crimping sometimes.. but yeah i definitely can share you my pololu code.

Love the paint job!



I haven't gotten into the servo side yet, but those sound like good ideas.

Maybe a continuos rotation servo, but I can see where the fear for crimping comes in. Maybe a continous rotation servo with rack and pinion to make the cable stay linear?

Idea...
Maybe you could break up the main hinge into two parts (seperating the pull arm) and add a gear reduction connection. You would have to add another pivot for this and the cable pull will be reversed, but it could work. It will use more torque to pull thou.

Like one of those baby toys that you slowly push the top button down and the cylinder inside spins like crazy.

Here is a diagram of my thought on this (generic drawing for design protection, but it gets the point across).


jayjayn,
I have an idea on how to get those hinges of yours fixed, too. I'll send a PM.
thx a lot, the paint could be better but im happy for my first time.. i'll post up detailed pics here when i get a chance , but i do love your helmet even though its extremely tight on my head but positioning the cables further back over my ears or behind it makes it perfectly fit on my head.

I really love the gear idea a lil worried how it will fit inside the helmet but i was thinking that similiar idea as well, just trying to figure out the best solution without buying more expensive servo's or actuators and realizing they won't work is a bummer.

The one thing i wish i knew was how much pull force do i really need? i don't know how to measure the amount of force needed to pull it open.

I have thought about continuous rotation servo's but i realized the problem is it will keep going so it will be putting a constant force when the helmet is fully open it will constantly trying to pull the faceplate and that will be draining power and killing the motor.. i assume that since there's no end point.

hmmmm...ive been thinking, are servos the only and easiest option if we want want to motorize an iron man helmet hinge? surely there must be something else that works like it or something similar.
Yeah i wish there was, i've been researching about linear actuators and even Muscle wire, interesting stuff.. but the problem about linear actuators are the speed , size , torque, and price.. and it doesn't seem too feasable to be used, and muscle wire would be amazing to use but i don't believe it can hold its position or have enough torque to pull.
 

MightyJohn

Active Member
hmmmm...ive been thinking, are servos the only and easiest option if we want want to motorize an iron man helmet hinge? surely there must be something else that works like it or something similar.
I've heard someone used the device that opens/closes a DVD player. I bet the device that drives a printer would work too. But like jayjayn said, its how to make it compact enough to fit into the suit. I think I sold myself on using gears to reduce the pull length.

Once I finish my larger helmet (one that fits me), I'll be more motivated to investigate the motorized faceplate. Hopefully in a few weeks.
 

rockeagle2001

Well-Known Member
Hmmm... how about a Tamiya Forklift system? Or a Tamiya Pulley system? Thats the one ive been looking at. For the forklift system, its kinda bulky but i guess, if you are doing a war machine suit, it will have enough space in it. But the action will be rather slow. In the pulley case, im guessing it is fast enough, and it can be turn on and off, but it just keeps turning and turning, so im guessing you'll either need a manual kill switch or the like
 

jayjayn

Well-Known Member
good suggestion, but the problem is the pulley needs to have enough torque to pull the faceplate and also at open to stop pulling and hold it there, if we would to do a kill switch to stop the pulley i assume it will just reverse back because there is no power holding up. Utilizing a wheel and maybe a fish line like Mockle used would work compared to how im currently using brake cables, the only issue i see from trying that is mightyjohns system needs resistance from the cables to push back the faceplate close.
 

jayjayn

Well-Known Member
Re: Iron Man Helmet motorized hinge problems [vide

Anybody else have input on alternatives to servos or a better servo to use? mightyjohn is already working a solution to reduce the amount of distance and hopefully that works =)
 

pRoJectEarth7

Well-Known Member
Re: Iron Man Helmet motorized hinge problems [vide

Anybody else have input on alternatives to servos or a better servo to use? mightyjohn is already working a solution to reduce the amount of distance and hopefully that works =)
dude i talked with quovadis0920... he said you have not talked with him yet... im pretty sure he may have some helpful tips to solve your problem with the motorization... he'll be making a tutorial for this very soon...:):thumbsup
 

jaymay023

Active Member
I would say you need longer servo arms as suggested above, also try different mounting points on the hinge itself.
Its all geometry and finding the correct fulcrum point.. I dont use cables or pushrods for my system cause i figure its extra stuff that can go wrong. Plus i can get a full 180 rotation out of it. Ill take a look at yer vid on a PC tomorrow and see what else I can suggest

Btw Im also using a pololu controller as well..


Sent from my X10i using Tapatalk
 

jaymay023

Active Member
Are you using a splitter for the servos? Its hard to tell. That will weaken the pulling power.. I know the pololu chip i have doesnt operate more then one channel at a time, meaning that you have to step move each servo individually millisecond by millisecond.

Sent from my X10i using Tapatalk
 

jayjayn

Well-Known Member
actually i was using two different channels for each of the servo's but i ended up going with a arduino setup instead so i could have more control, and ordered stronger 15kg torque hinges , with the help by john i think i figured out a solution to it.
 

jayjayn

Well-Known Member
I also luckily have room in the helmet to put in my new servo's and the new design on the hinges seem to have made a improvement on the pull but im still running tests if this will actually work.



 
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