Hi Patrick, thanks a lot for those detailed reports! - DirkS Patrick van Gompel <patrick_van_gompel@xxxxxxxxxxx> hat am 14. September 2011 um 19:46 geschrieben: > > I fixed the wheel today and did some more testing. > With the fixed rocker arm and strings to the swing arms it works sweet. The > simple setup of bolts and nuts as pivot points for the strings is working > fine, although I probably need to adjust it a bit for better durability. > I did a bunch of heavy brake runs. If the pavement is ok and I brake hard, the > bike stays stable, but it is hard to stay in the seat. If you go a bit forward > out of the seat the back of the bike will come loose. If I manage to stay put, > the front wheel did slip sometimes. But this is at maximum braking and is > quite a bit more than I can achieve on my mountainbike. The weak point of a > leaning delta trike is when the front wheel is really blocked by the brake and > it slips for a longer time. When going straight over a field of grass while > slipping, makes the trike rather hard to handle (leaning and steering). When > going over dirt/gravel and going into a corner while braking, the front wheel > breaks out, which makes the rider fall into the corner. When this happens it > seems unlikely to recover from it, although you can put your feet down to > prevent falling to the ground. But, compared to a mountainbike when only > applying the front brake, the performance is likely the same. So for slippery > surfaces I do need rear brakes on my trike. > I tested how the trike reacted when leaning to the front. The trike becomes > unridable as soon as a shift in leaning to the right or left is needed. This > might be because you don't have the grip of the seat anymore to control the > leaning, but possibly the changed CoG has the most impact. > I changed the steering pivot angle: going up in degrees makes the trike more > relaxing to ride and going down makes it more aggressive. I think that the > wheelflop had the most impact on this. 65-70 degrees seems like a sweet spot > to me. > I tested the use of the handlebar for leaning. It is only usefull for stopping > and keeping the feet on the pedals. Steering the leaning when cycling didn't > feel right and was even dangerous when really trying to. > > All in all I tested quite a few settings, but it's really hard to get an idea > what does what. There are so many variables and while you adjust one, a few > others might change too. So if I would make another trike, it would be hard to > optimize the design without changing the feel of the ride. > For example, I am still puzzled how the steering interacts with the leaning. > It is a bit hard to see how the trike leans when riding on it, but with the > handle bar for leaning I could feel which way and how much is was going. > Steering and leaning seems to go together like a natural thing. Even when I > tried to stay in the same position on my seat, the bike still seemed to lean > with every corner. I can think about reasons to justify this, but honestly I > have no clue. > > Anyway, I proved it is possible to crash the delta trike, but the feel and > stability is really what I wished for when I started to think about a trike. > Thanks again to Jürgen and Henry for sharing those great ideas! > Now I need some durability tests and get a fully loaded trailer hooked... > > Happy cycling, > Patrick > > From: patrick_van_gompel@xxxxxxxxxxx > To: python@xxxxxxxxxxxxx > Subject: [python] Re: Pythonjetrike > Date: Tue, 13 Sep 2011 19:56:30 +0200 > > > > > > > > > Hoi DirkS, > > A simple drawing: > > O frame attachement (pivot point rocker arm) > / \ strings to rocker arm > --------- rocker arm > | | strings rocker arm to swing arms > __ __ left and right swing arm > > > When you lean, the rocker arm turns around the pivot point so the strings > (between rocker arm and pivot point) will turn around that same point too (a > bolt fixed to the frame). The strings to the swing arm will move. One goes up > in the picture, the other goes down. Those strings will turn around bolts too. > Since the rocker arm in this setup is attached with string to the frame, it > will bounce against the frame when the rear is lifted. I didn't like that, so > I changed the strings from pivot point to rocker arm back to rod ends again. > As Henry describes on his website: it doesn't matter whether the rocker arm > and strings are horizontal or vertical. You can turn it around the swing arms > pivot point the way you like. See his picture: > http://jetrike.com/geometry/geometry-side.gif ; But horizontal was the easiest > setup for me. > Well, I made a handlebar for leaning. There were too reasons for that: to be > able to stop and leave my feet on the pedals and to use when something was > pushing the bike the wrong way (trailer or chambered road). Although the > handlebar works, it does feel kinda odd. But I must say I might have only > driven 10km with the bike and used the handlebar just a few times. It does > work to keep things level when you stop and you can keep your feet on the > pedals. Though, since the bike is so low to the ground, putting both feet to > the ground isn't a problem at all (and even easier than keeping them on the > pedals). When cycling with a proper setup (the relation between the one wheel > going up and the other down), I didn't feel the need to touch the handle bar > since leaning was easy to control with shifting body weight. But I did like > the other handle bar for steering, which could give the bike a very short > turning radius and gives easier control over shifting body weight. It's easier > to pull your body to the right or left with you hands then shifting weight by > just using your body. That is the main reason I like an handlebar on my normal > Python as well. > > Hope that explained, > Patrick > > > Date: Mon, 12 Sep 2011 21:24:35 +0200 > From: dirk@xxxxxxxxxx > To: python@xxxxxxxxxxxxx > Subject: > > > > > > > > > > > > Hi Patrick, > > > > > just to understand your routing completely: the rocker arm with its >screws/bolts on either side does not see any relative rope movement, it is just >the middle bolt(?) (on the central frame, not seen in the picture) where the >strings moves around when leaning? > > > I think whether the rocker arm is itself fixed or not and is either moving >with the wires or merely guiding them along could be quite a difference in >swing arm movement. > > > You are right with the "falling" wheels, this could be a supension >improvement, since the downward movement of the swing arm is completely >disconnected from the rest of the bike. > > Initially, i had a complete different idea of swing arm + rope >guidance(rocker arm) in mind. Your setup is quite a bit simpler since the >strings run horizontally, unlike my concept! > My thought was to have a leaver/handle somewhere that moves the strings >around to control leaning, but you are doing it completely by shifting >bodyweight. Is this working well? > > Greetings, > DirkS > > > > > > Patrick van Gompel <patrick_van_gompel@xxxxxxxxxxx> hat am 11. September >2011 um 18:39 geschrieben: > > > > > > > > > > Hey DirkS, > > > > > > > > I did attach a picture, but maybe it didn't come through. Here's a link: >http://cycle.free-creativity.com/images/strings.jpg > > > > It was just a testsetup and I have changed it to a fixed rocker arm again >now. I did went for another ride today with the strings between rocker arm and >swing arms. The feel was as great as with rod ends, no difference there. But I >had bad luck. I shifted back to the lowest gear, hit a bump or something and >the chain went inbetween sprocket and spokes. It did snap a few of the outer >spokes. I applied full front brake and I felt the back coming loose. I stopped >and bounced back into the seat. I checked the strings, but all was fine. I am >still amazed how fast you can brake. With a normal bike this might have gone >wrong, but here I felt rather safe. When I have fixed the wheel again I think I >will do some more serious brake tests. There seems to be a lot of reaction time >before things go really wrong. > > > > Now I think of it... with strings, both wheels can go down which might be >an advantage or disadvantage in certain situations. > > > > > > > > Btw, thanks for the fallback idea. I already had two strings, but >something like an extra safety line attached to a different point would be >good. > > > > > > > > Greetings, > > > > Patrick > > > > > > > > Date: Sun, 11 Sep 2011 13:37:47 +0200 > > > > From: dirk@xxxxxxxxxx > > > > To: python@xxxxxxxxxxxxx > > > > Subject: [python] Re: Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Hi Patrick, > > > > > > > > > > > > > > > > > > > > that was quick! > > > > > > > > > > > > You should use two strings in parallel, one as a fallback. Pulley with >bearing is important, otherwise i guess fun is very limited... > > > > > > > > > > > > you could have a simple leaver in the corner with two holes and split >the strings into sections so there are only straight part in all strings. You >would loose precision thought, especially with bigger ranges of movement. > > > > > > > > > > > > I think it is also a very lightweight solution. Could you provide us >with a picture how you implemented it so far? > > > > > > > > > > > > > > > > Greetings, > > > > > > > > > > > > DirkS > > > > > > > > > > > > > > > > > > > > > > > > > > > > Patrick van Gompel <patrick_van_gompel@xxxxxxxxxxx> hat am 9. >September 2011 um 21:04 geschrieben: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Hello DirkS, > > > > > > > > > > > > > > > > > > > > > > > > > > I tried your string theory today, as my new rod ends have not >arrived yet. It does work and seems stable, although I haven't tried it on the >road. I did bounce a bit up and down on the seat and made a short ride. It >seems to hold and is stiff enough. Though, I am not sure about durability, >since the strings do turn all the time around a bolt. A pulley/ball bearing >would be the proper thing, but for this load they are big. > > > > > > > > > > > > > The sound the string made -when touched like a gitar- is a bit scary >though. ;-) PING!!! > > > > > > > > > > > > > > > > > > > > > > > > > > Thanks for the idea, it is so much cheaper than 4 or 6 rod ends. I >am considering to keep them... Not sure whether I like a floating rocker arm, >but for the rocker arm - swing arm connection they might be a good solution. > > > > > > > > > > > > > Patrick > > > > > > > > > > > > > > > > > > > > > > > > > > Date: Thu, 8 Sep 2011 08:52:50 +0200 > > > > > > > > > > > > > From: dirk@xxxxxxxxxx > > > > > > > > > > > > > To: python@xxxxxxxxxxxxx > > > > > > > > > > > > > Subject: [python] Re: Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Hi Vi, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > nice Video, especially the last second! A raised position without >enough lean steer and the bike falls over... > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > the kettwiesel seems to work as a delta because the riders sits >way back with his cog near the axle/two wheels - and since this axle is >favoured through wheight distribution, it is the driven one. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I case of a python setup a driven front seems more attraktive >from this point of view, so a tadpole setup seems to be the right choice. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > My complicated lean steer idea was to have a central drive train >(typical python) that is distributed to either side with a rigid cross >beam(including differential) and then instead of mounting the two driven wheel >directly to this cross beam, have them connected like a suspended rear wheel on >a backward pointing leaver. In order to allow lean steer, the two leavers would >be attached to a downwardpointing string on the other end, that runs U-shaped >across to the other wheel. If you pull that string left/right you can adjust >the leaning. In order to stay U-shaped, that strin obviously needs to be guided >by another cross beam. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > The rest of the original python design could be kept as it is. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > This is somewhat the solution of henrys delta the other way round >to make it a delta and keep stearing and leaning independend. Instead of rigid >guiding rods, i came up with the string idea when i realised that a) >paraglider-strings a very tought, take enormous loads per cross section and are >stiff and b) you could have a suspension/damping unit between either side to >combine lean steer and suspension into one - all within a light setup. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I did not have the chance to try this out yet. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > greetings, > > > > > > > > > > > > > DirkS > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Vi Vuong <vi_vuong@xxxxxxxxx> hat am 8. September 2011 um 03:25 >geschrieben: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Sorry, forgot the link > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > http://www.youtube.com/watch?v=s9qt_XZDtcM > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >________________________________ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >From: Vi Vuong <vi_vuong@xxxxxxxxx> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >To: "python@xxxxxxxxxxxxx" <python@xxxxxxxxxxxxx> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >Sent: Wednesday, September 7, 2011 6:13 PM > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >Subject: [python] Re: Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >DW-TV clip on Hasebikes (in English) > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>________________________________ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>From: Patrick van Gompel <patrick_van_gompel@xxxxxxxxxxx> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>To: python@xxxxxxxxxxxxx > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Sent: Tuesday, September 6, 2011 10:49 AM > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Subject: [python] Re: Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Hasebikes uses a differential for their Kettwiesel. It seems >to be a limited slip differential, excellent for off-road. I was unable to find >a link, but saw this mentioned on a forum: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>"Haase is using the Gommier Tricycle differential unit with >an O-ring > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > inside to preload the spider gears. You can order them from >Gommier in > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Taiwan they come with axle tubes, bearings, diff, hubs, axles, >and disk > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > brake mounts for about $100.00 US. Several of our industrial >trikes at > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > work use the differentials. Call Lawrence at Gommeir and ask >him he has > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > all the details about the differentials." > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Not sure, but it might be this one: >http://www.arixworld.com.tw/en/products/?method=detail&aid=34 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>100$ seems very cheap. Last time I checked for differentials, >they were like 500. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Freewheels might be easier/cheaper, but for tight turns it >can be a nightmare since the inner wheel is driven but hardly moving. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>I might be wrong, but I think that Vi means that two front >wheels can be put closer to the CoG because it is not limited by ones leg size. >On my Python I can't move my front wheel closer to the CoG because then my >balls will have serious problems ;-) > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>I don't have the problem that my bike tilts forward when >braking, but I can make the front wheel slip when pushing hard on the pedals. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Good luck with your project Vi, I am curious about your >design. Please let us know. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>I was just thinking... with two front wheels there's no more >wheel flop! But does that mean that now the rear part > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > has to flop? That would be inward of the corner for most of >your body weight! That's very good, right? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Patrick > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>________________________________ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Date: Mon, 5 Sep 2011 22:25:02 +0200 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>From: bepb@xxxxxx > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>To: python@xxxxxxxxxxxxx > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Subject: [python] Re: Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> Hi Vi, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>I don't think that the tadpole will allow to put the front >wheels > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > closer to the CoG. I think the limit is more or less the >same as > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > with the delta. If the CoG is to close to the front >wheel(s), using > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > the front break can result in forward tilt, you might even >hit the > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > ground with the chain wheel. Going downhill will make >things worse. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>By the way, while a differential is the common solution for >cars, I > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > think maybe a freewheel on both wheels might serve better >and may be > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > easier to come by. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>In fact, a differential without additional precautions, works >to > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > have equal torsional forces on both wheels. If one wheel >slips it > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > will take away the power from the other wheel. You get >stuck if > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > either of the two wheels slips. This is why a serious >off-road car > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > has differential locks. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>You are certainly right about the fairing for the delta rear >wheels. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I guess either you have an enormous tail fairing or the >wheels have > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > to go with out fairings. Or maybe with separate fairings. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>Gerald > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>On 4.9.11 21:58 , Vi Vuong wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>Hi All, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>Yes, let us limit ourselves to FWD and pivot turning >mechanism, and leave RWD aside on its own. Tadpole front wheels can be covered >by the front shell piece / fairing, while delta rear wheels cannot be covered >by the sharp tail of a streamlined shell. With a differential, in case one >tadpole wheel slips, the other wheel can keep going. Plus tadpole wheels can >be placed closer to COG for more traction than delta wheel, especially with >bigger wheels / shorter riders. I am wondering if term "reverse trike" should >be clarified as FWD tadpole is like a reversed FWD delta, and vice versa with >RWD tadpole and FWD delta... > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>Yes, steering/braking is complicated with load/speed >involved, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > and may be just as difficult to build as FWD >differential. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Regarding control, I am hopping that steering 2 wheels >with my > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > feet would be easier than 1 delta wheel. Theoretically >more may > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > be better, but practically less may be more? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>Thanks for the design primer pdf. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>Vi > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>________________________________ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>From: Patrick van Gompel <patrick_van_gompel@xxxxxxxxxxx> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>To: python@xxxxxxxxxxxxx > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Sent: Sunday, September 4, 2011 11:33 AM > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Subject: [python] Re: Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Interesting discussion. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Probably you guys know, but I found this document > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > very usefull for trike setup comparisons, >steering > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > angles and other stuff: >http://www.hellbentcycles.com/trike_projects/Recumbent%20Trike%20Design%20Primer.pdf > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>I was wondering this statement too: "With 2 front > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > wheels driving/steering/braking, we should >get more > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > traction/control/stopping power." > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>-Not sure why 2 front wheels give better control. If > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > you have all the right angles for both >wheels it > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > might, but if you have not, it probably >makes things > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > worse. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>-Nowadays any decent brake has more than enough > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > power to stop the wheel. So having two >front brakes > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > instead of one wouldn't make much >difference. What > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > does matter is where you CoG is positioned. >Usually > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > it is easier to flip over the two front >wheels of a > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > tadpole than over the one more foward >placed front > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > wheel of a delta. And, having one front >brake is > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > less complicated than having two. A lot of >tadpoles > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > seem to suffer from 'brake turning' (or >what is the > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > proper word?). > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Gerald, there is another thing to consider (your > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > last point). Although your legs bent to the >inside > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > of the bent, your front wheel contact point >goes to > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > the inside as well. So your CoG might >actually move > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > to the outside of the bent. Of course that >depends > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > on the construction of your bike and the >rider. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Patrick > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>________________________________ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>From: bepb@xxxxxx > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>To: python@xxxxxxxxxxxxx > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Date: Sun, 4 Sep 2011 19:48:40 +0200 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Subject: [python] AW: Re: Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Hi Vi, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>there is a strong point in the curiosity, no > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > question. Its been the reason I have >been > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > thinking about a tadpole python myself. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>The shell for the delta somehow need to adapt to > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > the bending off the trike, but in which >way > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > could a tadpole python solve this >issue? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Concerning driving I dont see where the FWD > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > tadpole has an inherent advantage. The > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > additional contact area will be >nullified by the > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > less load per area for breaking and >driving. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>I like the considerations about the placement > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > off the solar pannel. In my case, I >should place > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > the panel on the back. I generaly drive >in > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > westery directions in the morning and >easterly > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > coming home from work in the evening. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>There are some sources comparing tadpole vs > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > delta on the net, but they seem to have >in > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > common that they focus on LWB deltas vs >SWB > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > tadpoles. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>But there are some huge differences between a > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > python delta and a LWB delta. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>*On python trikes, the load is significant more > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > on the front wheel. You need this to >avoid wheel > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > slip. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>*I dont think that there is need to have the CoG > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > (Center of Gravity) any higher than >with a > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > tadpole. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>*On the python trike, the frontwheel actually > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > tilts because off the pivot angle >0~50*. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>*Since the steering involves moving the legs to > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > the inside off the bent, weight >distribution > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > should improve, certainly over the LWB >delta, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > most propbly also over the tadpole. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Maybe we need a python trike based comparison? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Gerald > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -----Urspr?ngliche Nachricht----- > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>Von: Vi Vuong <vi_vuong@xxxxxxxxx> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>An: "python@xxxxxxxxxxxxx" <python@xxxxxxxxxxxxx> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>Gesendet: So., 04. Sep 2011, 06:13:58 GMT+00:00 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>Betreff: [python] Re: Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>Hi Gerald, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>With 2 front wheels driving/steering/braking, we should >get more traction/control/stopping power. Tadpole also fits nicely in a >standard streamlined shell, http://www.youtube.com/watch?v=jETRur5Bf58, but it >should be possible to achieve similar level of aerodynamics with advanced shell >design for a delta... > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>According to Lightfootcycles, the name tadpole came from >the "wiggling" caused by leg movements, similar to python PSI? They also have >a long pros/cons list, but seem to favor delta trikes (that they make) >http://www.lightfootcycles.com/trikecomp.php ; Henry (Jetrike) discussed in >depth on braking & turning, and favored the tadpole for larger tilting range, >http://jetrike.com/tadpole-or-delta.html. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>Cargo / weight distribution is another good deciding >factor for a delta or tadpole. If the load is a large flat solar panel in my >case, it seems that placing it up front would give better weight distribution >for a FWD. Plus having the electric motor in the rear tadpole wheel may be >simpler than in front delta wheel. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>Last, the curiosity factor of building a tadpole is huge >:) with possibilities of sharing frame/module with a exiting bike or delta >trike. Yep, the Guinea Pig needs one more module to go from bike to >delta/tadpole/quad, http://www.youtube.com/watch?v=0cy50C1Lhjw > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>Cheers, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>Vi > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>________________________________ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>From: Gerald <bepb@xxxxxx> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>To: python@xxxxxxxxxxxxx > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>Sent: Friday, September 2, 2011 11:27 AM > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>Subject: [python] Why a Tadpole? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>Hi All, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>It is not that I > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > like to >discourage > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > creativity - > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > inspired >by your > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > ideaes, I >have > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > been >thinking > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > about a >tadpole > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > python >design > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > myself. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>But actually what > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > specific >advantage > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > one like >to gain > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > from the >tadpole > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > python >design? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Just to >have > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > something >to aim > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > for. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>>Gerald > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >>>> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > http://dirk.steuwer.de > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > http://dirk.steuwer.de > > > > > > > > > http://dirk.steuwer.de > > http://dirk.steuwer.de ============================================================ This is the Python Mailinglist //www.freelists.org/list/python Listmaster: Jurgen Mages jmages@xxxxxx To unsubscribe send an empty mail to python-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field. ============================================================