Sort of tilting trike

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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.
I had to have a look to see what mine displays in the top left corner - "Design". I guess this is just an alternative to "Model". Interestingly enough, I was met with a red ribbon that I have never seen before, "You need to update, etc". This was right on topic. Anyway, I followed the prompts and it updated.

I can echo Emiel's comments as I have see auto updating in progress before. The video would be showing the version that Lars was using at the time. Can be a source of frustration when you are learning. Wise to use the latest videos but there is always some imagination required when following tutorial videos. I find that many run too fast and you can't follow the cursor. Individual computer configuration and personal preferences also create problems. All part of life's rich tapestry - maybe.
 
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Not just the heading was different but design didn't show the same options within it. Cad is ridiculously non intuitive enough without such extra issues.
 
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Not just the heading was different but design didn't show the same options within it. Cad is ridiculously non intuitive enough without such extra issues.
Yes they keep changing it and for someone that is new with CAD, fusion 360 is harder to learn.
Best is, to use thef latest instruction videos on the fusion 360 YouTube channel. As soon as you have the basics, the rest will cone and then the changes of the interface isn't any problem anymore. But I don't like it. It breaks my work flow each time they change things.

I didn't use it for a long time and only tried it, but you can also look ad freecad. It isn't the best cad program and personaly I hate it, but it doesn't change that much and there is a lit of info available on YouTube.

One shape is also an option, but your designs, will be open for everyone. You don't need to instal anything, because it works in a browser.
I found it an easy to use program, but didn't use it for a while.

I still need to instal solid works on my pc. That is what I prefer over Fusion360. Still not my favorite, but way better.
 
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For what I now see, I don't have to build in Ackerman in the steering itself because of the tilt angles of the wheels. I need to check the mounting width ad the bottom for the right tilt difference.
I will use ad that point, the same system. So that I can move the bottom arms to the front and rear to tune the setup.
I keep tank steering, because that way I will solve the steer brake problem and the construction is easy to make.
I think that what you say, that turning it around on his design, will help a lot. Also a rear break will help. But for me tank steering is easier. To make.

I will start working on the design as soon as my current build is ready.
Time enough to fine tune it.
It will be a fun trike and not for daily use as I do with my current trike.
No suspension and all wheels 20 inch wheels.
 
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There is no better CAD program than the one you really know how to use. If that one does it all for you, you don't need any other. There are those who swear by any number of programs that you would personally never choose and you could spend all your time trying them all and not learning how to use any of them. In reality, they all do the same thing but in different ways. I looked at a few when I was trying to find a better way of doing what I wanted. I could only use my regular CAD program's 3D component for a specific purpose for employment that I once had, designing shade sails but, despite it being very capable, I could not get into using it for general 3D design. SketchUp is used by many but I had the same result.

Having said all that, everything we do, we do because of habit and there is no CAD program that you can approach for the first time and design much in the first sitting - or a few following ones. The more capable the program, the longer it will take to learn it. It takes time to implant things in the brain where they will, hopefully, become second nature. Your brain must slowly accept that what it used to do quite readily, the old habit, needs to be broken and replaced with the new habit. You have to learn the language in order to understand the process that you will have to follow in order to get it to do what you want it to do - most of which you won't really understand until you have had a go at doing something specific.

There will be an initial period where you will be trying many things and get frustrated with them because you hit stumbling blocks.
As Emiel said, YouTube videos are a good source of tuition but you need to choose one that is too old if you can.

There are many things I don't like about '360 but, compared to that which I have used in the past, it is much, much, easier to use once you get underway, and far more powerful. However, I won't be exploring that which I don't need to know and only using videos that I think will show me what I need to know to do what I want to do and I have settled on selected YouTube channels for guidance. I definitely won't be using Fusion 360's electronics component as I prefer KiCAD for that.

Use what you think is best and does what you want as life is too short to waste on learning a multitude of CAD programs and not producing anything. After all, you do the same with trike building, MIG, TIG, Arc or Oxy, as well as your choice of other tools, methods and designs.
 
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For this I agree, it doesn't really matter what cad program you use.
Fusion is very easy yo use, but other cad programs are also not that hard to use any more. Alot is changed. I started with cad programs tgat needed Unix to run and they only had pull down menu's. It was a lit slower working than now, where you can customize it to what you prefer.

I prefer solidworks, because it can do surten things better than fusion. But Fusion can do things that are terrible in Solidworks. I also do other things tgan only bike/trike design it it and for those things, is fusion not the best. For quads is Fusion better.
But for here, it doesn't matter. Use what you prefer. Fusion improved a lot the last year. The interface got a lot better.

I can see why people find fusion hard. The changes they made, where big and for people that never worked with cad programs, that can be complicated with the older youtube video's.
They came with new videos that use the new interface.

I share many files with others ad the moment. That works great with fusion. It is also easy to help people with their work or work togheter on things. That is why I use fusion a lot and do things in it, that I designed in Solidworks but moved to Fusion.
 
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Still struggling with the vagaries of Solidworks.
 
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Try fusion 360. Get the student version. There is a free version, but they limited it.
The student version is also free.

I just looked ad joints and it was an old video, but I know now how to set limits. Going to do that, so my model doesn't jump around.
 
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The patent doesn't show much other than how the concept is. It sadly doesn't explain anything.
That is why I put it in fusion and compare it with what I have now.
I still think that it is the angle of the wheels. The outer is more vertical, what gives a bigger turning circle and the angle difference becomes bigger with a higher tilt. That all is good, but there is only one problem. Ideal would be as all wheels, turn around the same point. As the wheels are parallel, than is that not the case. By a small angle, it and a big turning circle, is the difference very small, but by a smaller circle, it will be bigger.
As I put it in fusion, than can I see if the wheels are parallel or not.

I notcide that the lower arm, is moved further back, so I want to see the influence of that.

I will also look for mounting his steering different, so when you break, you can push, instead of puling.

I have still a lot to look ad. But I learn more and more of the system, what helps me to make a working design that will solve it or lowers the problem.
 
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With Alan's system the wheels have no option but to stay parallel. The pivots simply don't allow anything else. The lower link has to cope with a range of movement of the uprights so presumably is set somewhere near the middle of the range of motion. This will mean slight camber changes as the bars move. I note it was made adjustable at the bottom but central seems the obvious place for it. It would seem wise to set the inner pivot central but set the camber to zero at either end of the range of upright movement so that when it moves it doesn't go positive camber.
Using a two piece link at the bottom with a central space between the inner pivots ensures the inner wheel leans more than the rear and the outer leans less.
 
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That is wat i was thinking, but his drawing showed it to one point. That made that I wanted to check it. I still make a model.

Doing the bottom mount to the frame like he did, is easy and also makes that you have some tuning options.

With the limits in the rotation I can set in fusion, I can see how far the rotation goes, till it reaches its limits. Fiw what I could see, that wasn't a problem, but this way I am surten.
 
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Using misalignment spacers you can get plus and minus 25 degrees or so from a typical rod end. You can get thinner housing rod ends for a bit more. This assumes that no part of the rod end hits anything-else such as the mounting bracket. It's easily enough to say that on pulling / pushing the bars alone there's plenty of movement in the links but when you add in the lean my maths fails and your modelling becomes needed. From Alan's videos he looks to go to 45 degrees caster on occasion.
 
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The two pinch bolts and slit at the rear of Alan's seat are intriguing. It's as though he was experimenting with a pivot along the bottom main chassis member. Measuring from the screen shows the rear bit of orange tube is a smaller diameter than the bit with the pinch bolts as though it slots inside. The yellow bit jubilee clipped on appears to be only the chain management fastened on as an afterthought and nothing to do with the reason for the pinch bolts.

 
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I noticed that also that it can ho up to 45 degree. I looked ad it and you need a big angle, to get enough steering.

I thought it was because he wanted to play with his wheelbase. Langer or shorter to try different turning circles. His steering can be adjusted, but also changing his length, can have influence on the steering.

I was thinking and I have fount a way to make the wheels center better in a turn. It isn't perfect, but it makes the error a bit smaller. I also looked to get the wheels, self straighten more, just like Alan's trike does.
Both are simple to ad.

Here is a sketch from the side.


To start with the steering/ackerman center point.
As they stay parallel, the wheels will give some friction in the corners. Less than a conventional trike, but the lower that is, the better it is.
To make that gap smaller, I moved the link location up and above the top mounting point where also is the rotation point. I first had it ad the the center, so the wheels stayed parallel. By moving it up, it will make that the wheels start to point out as the trike tilts. You can adjust the amount on 2 ways. Moving the mounting higher, or moving it more forward or more backwards. Forwards makes that it will angle more, just like moving it up.
Only negative point, is that you get the wheels point out by just tilting and not steering. Slight angles, that isn't a probroblem, because the adjustment to get the wheels point to the same center, is very small and small angles will give a very small change.

The second thing is, is the caster. I would turn it around and do it like normal trikes and bikes.
This will help, to get the wheels straighten and ad stability. Moving the center of the wheel a bit forward, also helps. 0 is OK, as long as it is not negative.
By using Alan's construction, you can play with the caster and set it to your liking.

Overal, I am thinking of making the link between the front wheels a bit higher, so 't is just above the center of the top rotation point. I can see in the cad model, if it needs to be moved a lot forward or backwards to come close so the wheels point ad one center point.
For the caster I will use his system and try some angles.

One interesting thing is, is as I make the ackerman, caster and wheel base adjustable. Than you can set the trike for different types of tracks. Tight turns a short wheel base with a bigger ackerman. On wide corner tracks, the opposite, what makes it more stable in highspeed corners.
 
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I went with the ackerman first and it works.
This is as it is leve, The wheels are both parallel to each other.


in the folowing immage with a tilt of 30 degree, you see that the inner wheel tilts more and the other wheel points out.


I can change both angles very easy. As you want to make the tilt difference smaller, you need to keep the mounting points ad the bottom arms in the middle, closer to each other.
Than the wheels will have less tilt difference.

In the next image, you can see the way i changed it so the ackerman changes in a corner.

The red lines show the hight difference of the 2 rotation points. The higher the difference, the more the wheels start to point out in the front as it tilts.
There are 2 ways to adjust that. You can move it up or down, but you can also move the link between the wheels in the direction of the blue arrow. The more to the back, the smaller the angle between the wheels will be. This way i can finetune the Ackerman on the trike. I can change it, to the wheel base. By looking in cad, what the position needs to be, i can adjust it to a wheel base, if you want an adjustable wheel base.
As you don't use an adjustable wheel base, it can make it so it has the right length for that trike.

I need to look ad tilt and ackerman. to see what settings are best. With the ackerman i set it so the points cros ad the right point adn with the length of the bottom arms, i can set the rotation point on the right spot.
the arm length is only one time and will be fixed. The ackerman can change from trike to trike depending the wheel base.

Small tilts, so as the road is slightly tilted, will not give any problems. That ackerman difference is just way to small to notice it.
This system also only works as you tilt. But with the limited steering angle of the front wheels, you need to tilt. With this setup i can set it for a tilt of close to 35 degrees. But it depends on how yopu do the rotation points if you can do more or less. I will focus for about 30 degrees tilt.

The tilting system lowers the friction compared with a normal trike a lot. Tires will wear a lot less and the corner speed will go up.
with the ackerman compensation, this friction will be even lower and even go faster trough a corner. It doesn't need to be a lot. All tiny bits help to improve it.

The next thing i wanted to check was camber. But i don't need to change the model for that, i just need to rotate it a few degrees on the ground and see what it does.
But i chck that with center lines in the wheels, so i can determen the point in a corner and adjust tilt and ackerman.
Under and angle, those things will also change a bit. i want to set a camber of about 10 degrees. A slight camber just to help with centering the wheels.


Only disadvantage of this tilting system is, is that it doesn't walk that great. so lifting the rear wheel and walk with it, will give some problems. But that is for me not a problem. It is more a race trike than anything else.
 
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I made a mistake with Akan his trike. His wheels also point to one center point in a corner. His wheels steer along the tilt and his outer wheel also tilt les, so that wheel will also steer les and that way is his steering angle also different.
 
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It's good that the lean function generates this. Second image though. You have the lean function demonstrate this but the uprights are still upright. It's all lean and no turn. At a 30 degree tilt there's almost certainly going to be some steering input. Depending where those middle lower pivots are set the uprights could have gone from zero camber to max negative and be back on their way to zero again (if central) for a large amount of turn. ie Not just the lean is going to affect Ackerman but the amount of caster / turn dialled in too as those lower links effectively change length as you add turn. It could be that instead of setting the lower link in the middle of the caster range, it may be better to set it near the vertical setting so the more turn the shorter those lower links get and the more Ackerman is dialled in. Odd that Alan appeared to have his nearer the other end of the spectrum?! Perhaps that wasn't his final setting. Could you show that same model with differing turn / caster settings for the same 30 degree lean please? It'd be very interesting to see how much the steering adds to that. I'm suspecting turn will add more than lean as the lower links look to shorten more via turn than lean though as said that will depend enormously on where the lower pivots are sited in relation to the uprights.

Example A. Pivots towards front - opposite to uprights when vertical.
Turn adds ever increasing Ackerman as the links effectively shorten as more turn is added.

Example B. Pivots in middle of range.
Turn starts off adding to Ackerman but as more turn is added it first lengthens the lower arms removing Ackerman but then puts it back in as it goes beyond the lower link pivot mounting. Seems less than ideal from that point at least.

Example C. Pivots at rear end of caster range - opposite to max caster.
The more turn is dialled in the more it lengthens the rods and removes Ackerman. Again less than ideal.

The more the centre lower pivot is moved off the centre caster range the more is going to be demanded of the rod ends to articulate and it may ultimately be this that constrains the positioning. Shortening the uprights would help the articulation issue.
 
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The image shows one side, because I kept one side straight. Best yo show how it works.
Yes, as you tilt, you will do some steering input. That will not change the angle for what I could see. The distance stays the same, so only the amount of tilt has influence on the wheel angle to each other, just like the tilt of both wheels.
Just tilting makes that you still can ho straight, because you can play with the steering angle.
That doesn't depend on the tilt.

Caster is an other story.
Alan his way is different than I can ad caster. He needs to rotate it, so the bottom moves back.
That has as effect that as he tilts, his wheels will turn, depending the caster and the tilt. More tilt will cause that he steers more, but also more caster will cause that as he tilts, steers more. He needs to tilt, to steer, but the amount of steer is depending on both. He can tilt a lot and steer litle by using less caster. More caster makes that he can doesn't meet to tilt that much to get the same turn.

The mounting ad the bottom is probably there to tune it. He can move it forward, but that makes that he gets less steer and need to use more input from his steering to get the right angle of caster to get trough a corner. I think that he will change it as he changes the wheel base. Longer wheel base, less caster but also less steer. Less caster to keep the ackerman right.

Caster on the system I did, can't be mounted like Alan's build.
It needs to be 0 or moved forward.
The effect of caster is the following.
It changes the tilt a bit. So the outer and inner wheels will have a smaller difference in tilt. An other thing that will be changed is the ackerman. It will get a bit less ackerman. But because the caster angle will be very small and the steering input, will be limited, makes that the effect also will be very small. You will see bigger changes as you go for 45 degree caster. But 10 to 12 will be more than enoug caster. Moving the center of the wheel, slightly forward also helps with stability.
So a combination of both, will do the trick.
With the amount of ackerman and tilt I can set, makes that caster will be no problem.

Tilt and ackerman are to separet things in my design. I can setup the ackerman first and after that, play with the tilt angle, till the wheels point ad the same point on the ground.

The ackerman works as followed on this design.
As the wheels aren't tilted, the ackerman will be 0 and doesn't change with any amount of steering input. So for a trike that can be locked as a normal trike, this isn't an option.
The ackerman will change by the amount of tilt, as does the steering.
Say you set the steer in an angle of 10 degrees. Ad 0 tilt, you will have 0 ackerman.
But as you tilt, 2 things happen.
10 degrees of tilt will make that you get more steer than with 0 tilt and you get ackerman.
30 tilt, will hive you even more steer and also more ackerman.
So even do that you can steer whyle staying straight (limited), you need to tilt to use the system optimal.

With the exception that it can steer while upright, it will react quit cimilar to Alan's system.

Yes there is an effect on the ackerman by the amount of steering input, but your turning radius will also be influenced. The same way as that happens on Alan's trike.

As I ad caster, I set it as fixed caster, so everything will stay in line.
Changing the caster isn't needed. It does its job, just like a a normal trike.
 
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I noticed the break problem in the video. Ad 3:07 he breaks to make a corner and you see him correct 2 times.
I wish there was more footage of the trike and the breaking problem and how it rides.
 
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so only the amount of tilt has influence on the wheel angle to each other, just like the tilt of both wheels.
If the tilt induces Ackerman then surely steering will too as steering involves swinging the upright against a fixed inner point meaning the lower rods effectively shorten or lengthen altering the tilt of one wheel respective to the other.
 
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