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#21
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
On 3 June, 00:35, Andre Jute wrote:
THE LOGIC OF TRIKES an outsider's viewpoint Considering a lightweight trike like a motor vehicle is incorrect. The major problem for which you have identified is that the angle from the centre of gravity to the line between the outer front wheel contact and the rear wheel is too steep. Other than making the track wider or lowering the rider to which you dislike on both counts, there is the possibility of laterally moving the rider. A wide flat seat may be provided with grab rails to the side. The rider would need to relocate and brace for the corner using the outside grab rail. The simplicity of the system relies on the alertness of the rider for all cornering over modest speed. The steering bar itself could be used as the bracing just as it is when a racer laterally shifts the bicycle to enable pedalling through a corner. An alternative to the above is a relocating front axle, not nearly so good, but saving constant attention. The idea is that upon turning, the 'axle' is moved outwards so setting up a 'lean' in addition to what the rider does with his upper body. The most satisfactory system will probably consist of the relocating axle, relocating seat plus body lean which is partially induced with an automatic seat relocation. I'm thinking that seat relocation may be up to 200mm, axle at 140mm plus a further body lean at the shoulder of 200mm. If all this was done with a Jute height seat with a 6oomm track, would this enable sufficient cornering angle on a typical adverse camber? If the answer is possitive then the design may be considered. Else I'm thinking the track just has to be wider. If it could be done along my principles then how far could the machine be narrowed? Making the machine less than 500mm is some accomplishment when coupled with a high cornering speed. |
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#22
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
On 4 June, 21:54, Andre Jute wrote:
However, if we abstract all the complications and qualification and reduce a tilting suspension to the fishbone of necessity (that's a pun, don't sweat it), yes, you can imagine what I'm talking about. Try this: Imagine the digit 8 made up of four long equal-length laths of wood and three short equal-length laths of wood, pinned at all joints so that the thing is a folding mechanism rather than a rigid structure. Turn your 8 sideways. Now you have three parallel uprights in a row, and two parallel longer pieces per side connecting the central upright to each outside upright on that side. The central upright represents the chassis and the rider, in short the trike's entire payload. The two outer uprights represent the wheels. Two parallel arms from the centre payload to each wheel are the suspension wishbones, seen from the side. In a corner the payload will tilt. On your figure 8, tilt the payload, represented by the central upright. The wheels tilt, pulled by the links. Reset to level. Tilt the payload, represented the other way The wheels tilt, pulled by the links. That's it, a tilting suspension. All the rest is detail and compromise to make it work in the real world. How do you locate the angle of tilt? And where does the energy come frome to lift the rider back up? |
#23
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
On Jun 4, 10:01*pm, someone wrote:
On 3 June, 00:35, Andre Jute wrote: THE LOGIC OF TRIKES an outsider's viewpoint Considering a lightweight trike like a motor vehicle is incorrect. The major problem for which you have identified is that the angle from the centre of gravity to the line between the outer front wheel contact and the rear wheel is too steep. *Other than making the track wider or lowering the rider to which you dislike on both counts, there is the possibility of laterally moving the rider. * Yes, I mentioned this possibility to Bernhard. Search for "sandracing". A wide flat seat may be provided with grab rails to the side. *The rider would need to relocate and brace for the corner using the outside grab rail. *The simplicity of the system relies on the alertness of the rider for all cornering over modest speed. *The steering bar itself could be used as the bracing just as it is when a racer laterally shifts the bicycle to enable pedalling through a corner. The bench set is clever, though it will have to be somehow supported and then we're moving from the simple, lighweight chassis I first posited. Without the sort of drive contortions I mentioned in my post to Bernhard (a seat boom pivoted near or on the bottom bracket, a universally jointed driveshaft) the amount of possible movement will be small if drive is to be maintained. Frankly, I think just making the trike wider than the 44in/1120mm or so currently considered a wide track will do the job better than acrobatic contortions. An alternative to the above is a relocating front axle, not nearly so good, but saving constant attention. * Now this is a much cleverer idea, It might be possible to build the suspension onto a kind of pantograph, which will also contain the progressive spring which will further control the tilt. But all this is complication and it is going to weigh. The idea is that upon turning, the 'axle' is moved outwards so setting up a 'lean' in addition to what the rider does with his upper body. The most satisfactory system will probably consist of the relocating axle, relocating seat plus body lean which is partially induced with an automatic seat relocation. *I'm thinking that seat relocation may be up to 200mm, axle at 140mm plus a further body lean at the shoulder of 200mm. *If all this was done with a Jute height seat with a 6oomm track, would this enable sufficient cornering angle on a typical adverse camber? 600mm track is invalid carriage territory. I was thinking of 56 inches, to be certain to keep the entire thing under five feet; these are arbitrary numbers. Bottom of seat would be in the order of 360 to 420mm high. If the rider wants to sit with his back at a comfortable angle, the CoG of this trike will be 400mm or possibly up to 600mm above that of a typical fully reclining trike. You're not going to make that up with fiddling the axle a little this way or that and/or whole-body shifts limited by the need to keep pedalling. (Body lean I'm discounting as already accounted for -- this after all a comparison with existing designs, not a blank sheet.) If the answer is possitive then the design may be considered. *Else I'm thinking the track just has to be wider. * I think we're there. 600mm track was never a starter for a fast comfort-trike except of very limited cornering ambition. I define "fast" as touring speeds (downhill on a mountain, how fast do you want to go around which corners?), not racing or record-breaking. If it could be done along my principles then how far could the machine be narrowed? Making the machine less than 500mm is some accomplishment when coupled with a high cornering speed. I shan't be volunteering to be your test pilot. I think a narrow track as a parameter of "goodness" of a trike design is as counterproductive as the one which made the current crop too low for anyone except a contortionist to use. Frankly, whether your sideway weight relocation ideas are any good depends on how much heavy complications they add. But I like them as out-of-the-box-thinking. We have too little of that on RBT, a supposed technical conference, and too many morons running around trying to put a damper on our natural exuberance. Andre Jute A little, a very little thought will suffice -- John Maynard Keynes |
#24
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
On Jun 4, 10:12*pm, someone wrote:
On 4 June, 21:54, Andre Jute wrote: However, if we abstract all the complications and qualification and reduce a tilting suspension to the fishbone of necessity (that's a pun, don't sweat it), yes, you can imagine what I'm talking about. Try this: Imagine the digit 8 made up of four long equal-length laths of wood and three short equal-length laths of wood, pinned at all joints so that the thing is a folding mechanism rather than a rigid structure. Turn your 8 sideways. Now you have three parallel uprights in a row, and two parallel longer pieces per side connecting the central upright to each outside upright on that side. The central upright represents the chassis and the rider, in short the trike's entire payload. The two outer uprights represent the wheels. Two parallel arms from the centre payload to each wheel are the suspension wishbones, seen from the side. In a corner the payload will tilt. On your figure 8, tilt the payload, represented by the central upright. The wheels tilt, pulled by the links. Reset to level. Tilt the payload, represented the other way The wheels tilt, pulled by the links. That's it, a tilting suspension. All the rest is detail and compromise to make it work in the real world. How do you locate the angle of tilt? * In the simplest version the angle of tilt is directly proportional to steering angle; that's the point of equal length parallel arms. It's limited by bump stops, generally to something around 35 to 40 degrees. And where does the energy come frome to lift the rider back up? You're looking at the ultra-neddy description of a complicated mechanism. I clearly said, "if we abstract all the complications and qualification and reduce a tilting suspension to the [w]ishbone of necessity," then we get the explanation above. We can't have it both ways, idiots complaining that they don't understand the full version because it is too complicated and long because it needs to include so many factors, the more knowledgeable complaining that the neddy version is incomplete. But it's a good question. The righting energy comes from the road flattening after the turn, the self-centring geometry of the wheel angles in three dimensions, the stored energy in the springs, and from the rider's arm muscles. Andre Jute Visit Jute on Bicycles at http://www.audio-talk.co.uk/fiultra/...20CYCLING.html |
#25
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
Edward Dolan wrote:
"Bernhard Agthe" wrote in message ... Hi, Andre Jute wrote: [...] Here is my full post again; it is internally and externally coherent ... Please, don't re-post this. Any reader can go back and read the original - if you care, put it on your website and provide a link. Saves download time ;-) Andre Jute is a crackpot. Can't you tell the type when you see it? He only reads his own words and the more he sees them on various posts, the better he likes it. Andre Jute has all the coherency of the certifiably insane and he should be in a lunatic asylum. His dumb ass is not even worth kicking. [...] Ed Dolan hits the nail squarely on the head. -- Tom Sherman - 42.435731,-83.985007 I am a vehicular cyclist. |
#26
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
Edward Dolan wrote:
"Jeff Grippe" wrote in message m... "Andre Jute" wrote in message ... THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute big snip You've got to be kidding! If you ever wanted to convince me not to read any of your books, you have succeeded. Sheesh! When I first got into bicycling many years ago I read several books about bicycles that were also gibberish. Let's face it, the mechanical engineering types barely know how to write anything that you can make sense of. Tom Sherman writes extremely well for an engineer. He occasionally uses too much engineering jargon, but I suspect he is just testing our patience. I think he must have taken some liberal arts courses when at college. But Andre Jute is far more typical of the type. Reading what he writes turns your brain to mush. Well, I do technical writing for a living. On the other hand, André Jute is the published author of non-fiction under his own name, and fiction under the pen name Andrew McCoy. -- Tom Sherman - 42.435731,-83.985007 I am a vehicular cyclist. |
#27
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
"Andre Jute" wrote in message ... On Jun 4, 7:21 pm, someone wrote: Andre Jute wrote:. THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute big snip Jeff Grippe wrote: You've got to be kidding! If you ever wanted to convince me not to read any of your books, you have succeeded. Sheesh! Ed Dolan whined: When I first got into bicycling many years ago I read several books about bicycles that were also gibberish. Someone wrote: For what Andre was attempting to explain, a picture book would be so much better. Oh, I wasn't attempting. I succeeded. You and Bernhard got it, and the rest of those capable of understanding are silent because I got it right. The only thing you succeeded in doing was boring everyone out of their mind if they were stupid enough to read it. Those with brains, like myself, never even bothered to read it since we can spot a crackpot like you from a mile away. [...] Regards, Ed Dolan the Great - Minnesota aka Saint Edward the Great - Order of the Perpetual Sorrows - Minnesota |
#28
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
"Andre Jute" wrote in message ... On Jun 4, 5:43 pm, "Jeff Grippe" wrote: "Andre Jute" wrote in message ... THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute big snip You've got to be kidding! If you ever wanted to convince me not to read any of your books, you have succeeded. Sheesh! Sorry about that, Jeff; it probably isn't your fault. This is a tech newsgroup and I'm writing on a very complicated subject for engineers who already understand the basics. It would probably help if RBT could accept illustrations. No one in the world gives a damn about tilting suspensions. [...] Regards, Ed Dolan the Great - Minnesota aka Saint Edward the Great - Order of the Perpetual Sorrows - Minnesota |
#29
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
"Tom Sherman °_°" wrote in message ... [...] On the other hand, André Jute is the published author of non-fiction under his own name, and fiction under the pen name Andrew McCoy. Thanks for the heads up. I will stay away from those two names like forever. It is not that hard to get published these days. The real problem is getting anyone to read what is published. Regards, Ed Dolan the Great - Minnesota aka Saint Edward the Great - Order of the Perpetual Sorrows - Minnesota |
#30
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THE LOGIC OF TRIKES an outsider's viewpoint by Andre Jute
On 4 June, 23:30, Andre Jute wrote:
In the simplest version the angle of tilt is directly proportional to steering angle; that's the point of equal length parallel arms. It's limited by bump stops, generally to something around 35 to 40 degrees. I feel we're thinking of different things, I'm not certain what you're getting at. What are you attempting to explain? Perhaps a piccy will help. And where does the energy come frome to lift the rider back up? You're looking at the ultra-neddy description of a complicated mechanism. I clearly said, "if we abstract all the complications and qualification and reduce a tilting suspension to the [w]ishbone of necessity," then we get the explanation above. We can't have it both ways, idiots complaining that they don't understand the full version because it is too complicated and long because it needs to include so many factors, the more knowledgeable complaining that the neddy version is incomplete. How about using roller skate steering? The angular positioning of the rider would be assisted in location by the 'steering bar', the steering follows. To exit a turn, one straightens up using the bars and the steering straightens up. The steering inducer is also the suspension being a pivot in a rubber block. Clamping force compressing the block varies the steering response. But it's a good question. The righting energy comes from the road flattening after the turn, the self-centring geometry of the wheel angles in three dimensions, the stored energy in the springs, and from the rider's arm muscles. |
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