Sort of tilting trike

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When I was in my bed, I came to the conclusion that camber needs to be 0, but ackerman also?
That makes it even easier.
I was looking ad how to do ackerman and I had a solution, but that isn't needed any more.
The changes are very simple and then is the link between the wheels very simple.

I will make a model from that, today. Just a basic model but it will be clear how I would do it.
 
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Ok, this is without ackerman. I can easily ad it if needed.
I didn't ad the tank steering yet, but that is easy to ad.





The arm goes up in a corner and as yopu steer without tilting, it stays level.
Even as you turn the other way than turn, it wil not be a problem. But that will never happen, so there is space enough the let the Tank steering arms go under it.

Don't watch on how it is drawn and the scale, because i just made a simple basic model for the concept.
 
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I will ad an option for ackerman.
It is easy to ad in this. It will have very limited influence on the geometry, because the steering angle, whyle tilting is very limited.
He uses castor, but i can ad that if needed. Just move the lower arm a bit to the ront.
 
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After a little thought i think it does need some ackerman. I can't even begin to work out the maths of exactly how much it needs in a lean. It needs different steering input according to the speed on any given turn. Without a sophisticated model I can't envisage if a std ackerman set up will cope when tilted.

Example A
Trike turns a 20m radius at 2mph and is largely upright behaving as a conventional trike.
Example B
Trike turns same corner at 30mph and is very leaned over with much less steering input.

You need a system that puts in less ackerman as it leans. As it leans it will naturally require less steering input which will also equal less movement due to ackerman so there's every chance a std ackerman set-up may do. A 3d computer model will tell you if that's right.
 
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I looked ad his system and his tilting has some influence on his ackerman. That is way less in his I do it. It isn't perfect, but because the more tilt, the less steering, the error will be even lower.
So I don't see a problem.

I will ad it tonight.
I added tanksteering on one side, but I need to check motion in fusion, to see if I can ad collisions and limits like other cad programs I worked with.
Now it flips all directions, do it isn't easy to use.

Maybe some fixed connections that I can adjust by changing parameters.

As you ad a locking system, you can ride it like a normal trike. Maybe easier as you need to stop a lot of ride in the city in bissy traffic.
 
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It is hard to see, but it works. The Ackerman gets bigger with more steer and isn't influenced by tilt.
Especially nit by a small amount of steering and a lot of tilt.
Only problem is, is that for riding without tilting, this will have a very big turning circle.
I can solve it by changing the tank steering.
Looking ad the amount of Ackerman it gets with steering under a big angle, makes me think that even with that it is better, i don't see the real need for it. Only as you don't tilt and steer more ,akes it usefull.
But for that i need to make some design changes to the tank steering setup, so the wheels can turn more.

I think with a 20 inch rear wheel and a short wheel base, that the ackerman will be a bit bigger than i have it now. but the influence stays very limited. In the first few degrees, the ackerman effect is very small.
Caster has probably a bigger effect.
 
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If you have any caster that will also steer as you lean and will add another variable to the equation screwing up the ackerman. Equally without any it won't self centre. You may have to experiment and see if a compromise position can be found. Compromise was always on the agenda when I built the MK2 - everything was compromised at some point in the motion as there was simply that much of it. The rod ends will have to cope with the usual range of motion in the steering linkages plus the range of motion caused by the tilting and it's quite a big range for any rod end to do. The outer ones will be the most affected. Perhaps rod end misalignment spacers will be enough. I'd suggest that at a minimum they'll be necessary and you may even need extra thin housing rod ends to allow more movement. At worst you may need to limit either the steering or leaning to stop the rod ends hitting their limits. A tilt lock is a simple enough thing with part of a disc brake on the main chassis to axle tube pivot operated by a friction gear shifter.
 
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There is still a lot to find put on how it works.
I can copy his design and ad tank steering and that will solve the steering problem and ride like his trike. But I don't know if his trike was good or because of the small steering angles and the amount of tilting, that it wouldn't mater that much and that the wheels wringing in the corners, was limited by the size of the tires he used.

For what I see now, is that as I make the lower arms shorter, the inner wheel tilts more than the outer wheel, what makes that he compensated that way for the lack of ackerman.
It also resulted that the tires would wear a bit faster, because the distance between the wheels where they tough the ground, becomes smaller.
Not much, but it gives some friction.
I don't think that it is a big problem and lesser of a problem than the friction that you have in a corner on a normal trike.

There is a lot to look into.
I think with changing the bottom arm lengths, that I can remove the ackerman setup.

Those balljoints us something I was looking for.
As I make that you need to tilt, to steer, than they aren't needed. But as you make that you can ride it as a normal trike and a tilt trike, those are sertenly needed ad the linking system of the wheels. Only because of that the angle of steering whyle tilting is way less and with the way I mounted them, they rotate enough.

I will look and test tomorrow more.
I noticed that ad an angle of about 30 degrees tilt, the inner wheel, tilts almost 3 degrees more.
I will see what te difference will be with shorter arms ad the bottom.

It is not jyst a system that you can put on a trike and it works. I understand why you needed to tune it each time. It is a system that changes in every angle.
 
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Interesting that the inner tilts a bit more and very fortunate. The thing about the rod ends hitting the end of their travel is that if they can then it's likely that at some point you will find a situation that they do hence my suggestion for stops to prevent damage. Unfortunately it'll very likely only be a combination of large lean and large turn together that causes issue meaning stops are almost impossible to put in place on any one function. You'll probably need to play around with mounting angles for the rod ends and their arms to get the best movement available. I'd suggest prioritising lean over turn (mounting the outer rod ends vertical) simply because hitting a limit on lean will exert a bigger force than on turn. If the leaning works as hoped for then turn will be minimal anyway, especially at speed. Better to hit any limit at very slow speeds where turn will be needed more than lean.

I'd have thought that a tilter will wear the tyres less than a non-tilter simply because it uses a larger area of the tyre and not just the bottom.
 
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With the tilting alone, the link between the wheels will have no problem and it doesn't matter how much the angle is.
The only way that they reach the limit, is as you turn the wheels. But the turning radius of the wheels with this design is limited and therefor it isn't a problem, especially not as you tilt a lit and don't need to steer a lot.
For the tanksteering setup, this can be a problem. I need to look ad it, but I think that I need other ones for that or an other system.
I need to look in to that. I modelled the links do I can check it in cad.

I think overal, that the wear will be less on a tilting trike, but the tires will rub a bit whyle tilting. But I think with the movement, that it wouldn't be any problem. Also gor what I can see, it is very limited.

I will remove the ackerman and play with some things ad the bottom arms.

I kept looking ad Maurer's design and he could change the setup. He could as more or less steering and as I see him ride, he keeps his handles forward and didn't adjust it to steer more or less. He does that mainly by the angle of tilt.

I don't know how much tilt he has, but I get 30 with this design and dimensions. It is limited by the frame. I can change it, so I get more tilt, but I don't know if I need it.
 
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I believe a two wheeled bike rarely gets above 45 degrees in a professionals hands. Above this figure most bikes move from positive to negative trail though it varies from bike to bike. At that point they become unstable. A trike is less likely to become unstable and also has greater contact with the road. Equally shifting the riders weight is probably easier on a trike than bike so leaning slightly off the trike will allow it to lean slightly less than would otherwise be needed. I would expect 30 degrees to be enough.
 
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As I see the angle, than I also think that Maurer his trike is also about 30 degrees. I have a little bit left and moving things a few mm around, give more space for tilting, but I think that it will be enough to start with, especially for testing.
As the system works good, than changing the design a bit to get more tilt angle is always a possibility.
 
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I just uninstalled it as I didn't get any use from it being too complex. Pictures will likely do.
I note your comments Popshot. I saw Fusion 360's potential compared with another CAD program that I purchased years ago but never got into its 3D potential, seeing it as too complicated although I always suspected a fundamental misinterpretation of How or What.

I watched many tutorial videos but also found Fusion 360 more than a little challenging where I was able to sketch a few things but then had difficulty editing them later and no design turned out exactly as expected or wanted. Problems were probably caused by the brain's automatic association with my previous CAD program. Very frustrating. It was only after watching Lars Christiansen's
video that it all started to click. It made a big difference as it identified and fixed a fundamental misinterpretation.

Within an hour or two, I was able to satisfactorily model a 6-speed rear cassette and building up a model of my mid-drive. I'm now sold on Fusion 360 - with many things I won't be using, like its electronics design, and many things still to discover and use - and I thank Emiel for putting me on to it.
 
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I am not a fan from fusion, but it is the best free program by far.
But I am an engineer and worked with most big cad programs.
It is an advantage as you used an other cad program before. You will learn it faster, because you know what surten things mean. You only need to know the basics from it and after that, it is easy.
Fusion has a lot info online on how it works. There are many instruction videos, from beginners to experienced users.
Other programs don't have that, but I got every year several instruction days as there was something new.
 
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I had previously tried that video. It failed for me at the very first hurdle because my version didn't have "model" in the top left. I assume he had the paid for version.
 
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I had previously tried that video. It failed for me at the very first hurdle because my version didn't have "model" in the top left. I assume he had the paid for version.
No, fusion gets updates and you had a newer version. They change the layout a lot, what anois me a lot.
I wssed that they would solve some bugs and change some things, so it doesn't get weird errors, where other cad programs do what you want.
 
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I wonder if Alan ever tried it with the bar's steering link above the pivot so braking forces pushed the levers back rather than pulled them forward. Unlike almost every other tadpole this one seems like an excellent candidate for a good rear brake.
 
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I don't know. I think not, but uoh never know. A rear break would help. It lowers the pressure on the front a bit.
Also with pushing instead of pulling, will help a bit.
He talks about ackerman in it, so I will look ad that also.
 
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