Hello, I understand that you are a great engineer and the best person I know to ask this question: how do I understand what gear ratio to use in my transmission? I'm currently engineering a single seater car, I'm trying to make it as small and as light as possible and could really use some advice to potentially cut down costs on having to rebuild parts because of my lack of experience. I'd be very grateful to you for a reply, thanks in advance❤
Thank you. That is a complicated question and I’m not an expert on this particular topic. It depends on factors like the motor’s powerband, vehicle weight, shift time, and usage. For example, many cars with a high power to weight ratios have a very tall 1st gear. This is because they are traction limited and the additional time for the gear change would make the car slower. Cars with narrow power bands, like older F1 cars, might stack the middle gears very close together so they are at peak torque on the exits of particular corners. The only way I know of optimizing this is through simulation or modeling. I don’t know how, but I’ve seen Matlab or Excel used, and for more complex track based simulations something like Adams Car Simulator.
My enclosure is Masonite for now. It’s worked well, but fire is always a concern when active heating. I’ve bought an old server steel server enclosure that I will be moving it into.
Im my opinion way too complicated for what it really is , the design for functionality it’s just way too extra and NOT overkill at all because it didn’t work
the design is brilliant. i was looking at this type of design and following the bose system. the issue that always made this design challenging for me was not the design it self (in terms of concept) ... it was was the energy and the dynamics of it required ... this suspension in my opinion would require very high amps, maybe a 48v system running on capacitor as a quick charge and discharge, and a very large battery pack to back it up ... is suppose it could be easier to adapt it for a slower moving vehicle ... just some thoughts... looking forward to seeing how you overcome the challenges and reach your goals ... good luck
instead of a gear pump, you shall definitely take an ABS unit from a scrap yard, open it and try using the design features inside of it in order to create a small but powerful hydraulic pump. If you go that path, you should investigate a lot on reducing the pressure peaks as the flow of piston pumps is not linear unfortunately. All in all, I think piston/plunger hydraulic pumps are more fit to be printed using FDM and some postprocessing (epoxy sealing of the printed components)
I agree, I think piston and plunger pumps are the way to go. I had a lot of issues creating efficient valving though, I need more iterations. I thought about the ABS pumps, but size was the biggest factor. I would love to be able to fit this in an RC car of some kind. I think I can make a pump under 2” by 2”.
Try regular spur gears, rather than herring bone gears, most proper hydraulic systems use regular gears, and I think there would be allot less chance of the fluid ‘slipping’ Bach through the pump. There’s really no reason to be using herring bone gears as there’s minimal thrust loads
That’s interesting. Several places I read that herringbone gears have lower leakage losses due to the v shaped engagement. It was said they weren’t used because obviously they’re harder to make. Do you have any papers on this? I printed a set of straight spur gears I may try out here.
No, I don’t have any papers, but in my experience working on industrial hydraulics they’re all straight spur gears I may be wrong and the herringbone is just as good, but it would be interesting to see the difference.
You are a pretty awesome guy! Now you've got me missing racing school in Quebec in 1979. I remember they warned against "Gearbox Fever," which is when a trailing driver focuses on the gearbox of the car in front of him and ends up in the same accidents.
What your doing is really amazing! I have to laugh out loud when I hear these sidewalk critics writing TEN page critics of your work. Why don't "they" put in the time to do something intellectually constructive as you have done?
When I designed my version of torque vectoring model for my Master Degree I have used a mybrid between Akerman and Pithagoras derived equations :) my colleagues laught about the Idea but that worked smooth
That's interesting. Someday I want to comeback and create a more sophisticated mathematical model like that. I'm curious to see how much difference it makes. I need a lab setup to test that out though. There's too much variability in the real world.
I'm sorry to be that guy, but I am just curious of how much money would it take to make one adapted to a 2-stroke 100cc engine. Or, if it is possible to get the 3D print files. Thank you very much, I hope you have a wonderful day! Edit: I have a 100cc motorcycle that use sequential gear, no clutch lever. I'm thinking of building a gokart with the engine from my motorcycle using this gearbox, or, just a 1000cc 3 cylinder engine. Again, thank you very much!
The F1 gearbox model is available on printables.com under indeterminate design. I don't know how well this would adapt to a motor cycle. It would be quite expensive to manufacture a custom gearbox like this and the control electronics would need to be much stronger. The disadvantage of this gearbox is that if anything goes wrong you will engage two gears and lock everything up. Check out this gearbox, it's based off the Honda MotoGP gearbox and is probably a lot better suited to a motor cycle. Unfortunately it will still be very expensive to reproduce in metal. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-0GJrDS8-nbE.html
@@IndeterminateDesign I've got a lot of questions, I'm sorry. Would you be willing to answer them? Are the gears interchangable? As in, can I change the gearbox ratio? Thank you....
Control valves *should* have bypass when in "off" position. Extended periods of "off" while the pump is running will cause the working fluid to overheat.
Absolutely. I couldn't think of a way to do this with the disc valves I was using. I copied an existing design used in a lot of RC hydraulics. Next time I want to have individual electromechanical 3 way valves.
@@IndeterminateDesign Have a look at spool valves. They really aren't difficult too manufacture and provide all the functionality you want. Tractors, excavators, etc all use them.
Good idea, I think you would have more success with a piston style pump driven by a stepper motor, think leadscrew on a resin printer, it would be capable of generating serious amounts of force.
I agree. I used a 2 piston pump as my first prototype, but I lost the majority of the pressure in the valves. I need to try it again with some much more accurate SLA 3d printed parts.
Well done, man ! I love it. Thanks for sharing. You might find this MotoGP seamless gearbox interesting. It does not have shifter forks and if I recall, does not require a torque cut. Evidently, this is a 2013 Honda patent design. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-0GJrDS8-nbE.htmlsi=fbHxaQpVxoeDGC9E
what about a FDM surine like pump? so having one of that big suringes actuated by a motor an a theated rod with a nut, that will generete positive/negative pressure fluid to actuate the sistem.
Those definitely would work. I have tried a piston pump which is like a syringe but just resets. I had a lot of challenges with the valves. They need more development.
Hello ! I have no knowledge about hydrolics or robotics. But when I see the system I don't understand the advantages of going for hydrolics instead of electric actuator. As the power source is an electric motor, I think that the hydrolics are just a inefficient gearbox. What am I missing ?
In many ways it is just a gearbox. The biggest reason is power density. It’s very easy with hydraulics to achieve a massive mechanical advantage by just changing the area ratios between components. This allows for actuators that are much more compact and lighter than a comparable gearbox. Additionally, a single pump can service multiple actuators. And typically all the actuators aren’t using the full bandwidth of the pump so you have less redundancy.
“Reverse is very rarely used in F1” Well, if you’re allowed 6 gearboxes for the season, I’d guess that means you can reverse no more than 6 times for the entire season. They don’t seem to like being used twice, from what little we see of drivers attempting to use reverse.
Are you planning on taking it further? Im really excited for it! Would be awesome to actually get a hold of rc hydraulics without giving an arm and a leg!
I do want to develop this more, but I don't have a definite timeline. I want to try several different types of pumps because I think that is the hardest problem to solve at this scale. Once we can generate a couple of hundred pounds of pressure, the rest I think will be much easier to solve.
Great video . I used to machine and maintain hydraulic pumps professionally, this looks like a professionally made system . On another note fdm can manage parts like this , however there will be fitment and size limitation .( Gotta be large enough so that part tolarances are within the available tokerance of the printer ) i gotta get my hands on an resen printer.
That’s awesome. I agree, all the FDM pumps I tried had to be much larger in size. The stretch goal is that I could fit a hydraulic system into an RC car. In hindsight I should have started larger and worked my way smaller.
Micro hydraulics seem like an idea with high potential, but i always got the feeling you had to "know a guy." I am really surprised that robotics haven't used more of it with how easy ratios are with piston vs pump size. This seems way more accessible imo, thanks.
I was trying to figure out the same thing. The cost is quite high for the off the shelf parts. I know some places like boston dynamics have used these, it maybe just a money thing.
I’d need to dig through all that again, but look for patents from Xtrac and Graziano on seamless shift gearboxes and you will find them. Also, sometimes look for the individuals listed on the patents, they often patent the F1 stuff under shell company names.
Cool project! The 3D models make the parts seem so much bigger than they are in reality, at least to me lol. I really like your modeling philosophy of building the flow paths first and then subtracting them from the solid manifold. Well done!
Mini hydraulics parts for convertible cars are actually pretty cheap, also mini pneumatic cylinders work for hydraulics. Pretty cool though especially for a part that isn't something you can get off the shelf.
Yeah, you can definitely buy something similar off the shelf, but not as small or cheap. My hope was to be able to miniaturize it even further. I’ll look more into pneumatic cylinders. I found a lot of cheap ones on aliexpress and I’m curious how well they work.
Great project! At some time I was going to try something like this too. Similarly, my idea would be to 3d print the channels and blocks but size the prints so they could be contained in stock profile metal sections. Doing this might help increase the working psi as the pressures could be transmitted from the fluid, through the print to the outer metal casing. Also, research might be needed into which hydraulic fluids can be used which won't erode the 3d print materials. Simple veg/sunflower oil might be all that is needed. My idea was to incorporate 3d printed channels for a hydraulic spool for controls and a hydraulic 360` rotating turntable junction such as used on an excavator but contained in stock metal sections.
Yeah. I think something like vegetable oil would be even better. The CHF11 I used is plant based but really thin compared to a vegetable oil. That’s an interesting idea about encasing the 3D print in metal. What kind of pressures were you trying to achieve? The passage ways in my setup are just 3mm or 1/8” and based on the strength figures for the resin that should handle close to 1000psi. But it probably doesn’t do that in the real world.
@@IndeterminateDesign resin as liquid in tested in a hydraulic press might achieve that sort of pressure. However, solid resin uncontained, is still likely to fail on the layer lines. My project still hasn't even started! However, I'm not expecting large pressures. You might find that you can indeed lift 1kg or more with the identical set up that you have but substitute a much larger bore cylinder. Lifting the load will take more time and more fluid but the system should cope. Possibly the "best" type of pump would be like an internal combustion engine in reverse - as used in construction cement pumps. Such pumps can generate huge pressures and hold the load when the pump is stopped
In addition to tolerances that floating side plates address, those standard herringbone gear shapes will allow a leakage path that effectively joins suction to pressure. If you study commercially available helical gear pumps, you will observe that much like on a screw compressor the geometries are designed with care to minimise the leakage path at the meshing point.
I had debated that. I had read herringbone gears had less leakage, which may not be the case. Do you recommend a spur gear? Any particular pressure angle?
Would you consider doing a video dedicated to the breaking system. I would like to know more about how you stop and ABS that you have designed. You make awesome videos, and I love the projects. Keep up the great work
I would have thought a radial piston pump would work best for 3D prints as the o-ring gives a lot of leeway. I would probably cheat and use a metal cylinder 😂. It does add a lot more valves, though.
I think a piston pump would work really well and I worked on building one for a long time. I did have to use metal tube liners in my test prototypes. It was the valves that killed it. I think with SLA prints I could have gotten the valves to seal better, but FDM was horrible.
