Paul Turner
|
| posted on 26/12/11 at 10:44 AM |
|
|
Arn't a lot of these boxes on small cars the variomatic type with set belt positions when you go to the paddles and not true manual boxes with
an auto mechanism.
Just spotted the link between Citroen, Smart and Alfa, they are either low powered, unreliable or both. Seems that reliable powerful cars use a
propper auto if you must have one.
Real cars have manual boxes, totally reliable, why mess about.
|
|
|
|
|
l0rd
|
| posted on 27/12/11 at 02:21 PM |
|
|
have a look at this
linky
|
|
|
snakebelly
|
| posted on 27/12/11 at 04:15 PM |
|
|
and no sign of a price anywhere! guess that tells us all we need to know...
|
|
|
eddie99
|
| posted on 27/12/11 at 04:16 PM |
|
|
Just found the price on their website, looking at 4k dollars..... Cheaper to buy a sequential box!
|
NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
|
Paul Turner
|
| posted on 27/12/11 at 04:30 PM |
|
|
How is that little lot going to fit in the tunnel on a seven, just about enough room for the gearlever and reverse light switch in mine.
|
|
|
CNHSS1
|
| posted on 28/12/11 at 11:16 AM |
|
|
Ikeya have been doing these for various jap boxes for years
http://www.nengun.com/ikeya-formula/sequential-shifter
"Racing is life, everything else, before or after, is just waiting"---Steve McQueen
|
|
|
v8kid
|
| posted on 28/12/11 at 01:57 PM |
|
|
Ok done some back of fag packet sums and checked out requirements.
The highest force requires at the gearbox end of my UN1 box was 180oz with a 4" lever. Googling servo motors advice is to double the load when
speccing the rating.
On ebay there are CNC steppers for £19 that give 1.2Nm (170ozin).
Also available are T5 timing pulleys and belts for a few quid.
So with a 4:1 belt drive reduction ratio and if we make the servo lever arm 2" as opposed to the gearbox 4" that will give 1360ozin and we
need 720ozin so it is just shy of double the load.
the gearbox arm moves through 20 degrees when changing from 1 to 2 so the stepper will need to move 160degrees. the stepper has 200 pulses per rev so
to change from 1 to 2 requires 89 pulses which f the change is completed within 0.25sec is 356 pulses per sec - well within the motor specs.
Tons of diy or cheap ready made controllers available based on pic or arduino that can be pc programmed or we could use a raspberry pi!
So with some ingenuity buying all new parts its there for less than £100.
Further linking to road speed and engine speed no gearchange lever is required just actuate the clutch and the processor knows whether to change up or
down. Just like Jenson's gearbox!!!!
Cheers!
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
|
|
|
MikeRJ
|
| posted on 28/12/11 at 04:33 PM |
|
|
FWIW I know someone that made a "twini" Metro Turbo, i.e. fitted another front metro subframe, engine and box to the rear of a Metro, just
like John Coopers famous Twini. To solve the gearbox issue he made a simple robotic change for the rear engine which used windscreen wiper motors as
actuators and micro-switches as limit switches. There were also micro switches installed in the remote gearchange. It sort of worked, sometimes, and
with a bit of development it might have been made better.
One of the problems is the total lack of feedback, both to the controller and the driver. With a basic system the motors can't tell if the
synchromesh is baulking the change (e.g. if the clutch was dragging) and will simply continue to force the box into gear. With no feedback to the
driver, he has no way of knowing if the change was successful, so has to assume it's ok to release the clutch some time after the change. If it
didn't work for any reason, the box may be only partly engaged when the clutch is released, at best causing nasty grinding noises but
potentially a safety problem if you suddenly have no drive right when you need it.
These issues could be worked around by providing positional and force information back to the controller and back to the driver, perhaps by locking
the clutch down until the change has completed, but would make an already complex system more complex. The robotised boxes have control over the
clutch which removes this issue to a large extent, but explains the slowness and reliability aspects as the control system has to constantly judge the
biting point which shifts with temperature and as the clutch ages.
|
|
|
MakeEverything
|
| posted on 28/12/11 at 05:11 PM |
|
|
Thanks for the info. We're drifting into complexity now though.
My car isn't a seven, but I also was just looking at a mechanical means or "ratchet system" to see If it's possible to convert
a standard UN1 to a sequential in tune with the locostbuilders ethos. Manual clutch is fine, as is manual gears for feedback and drive ability
purposes. If this means a redesign of the primary shaft and gear arrangement, then that's what I was looking at in the first place.
Kindest Regards,
Richard.
...You can make it foolProof, but youll never make it Idiot Proof!...
|
|
|
iank
|
| posted on 28/12/11 at 05:47 PM |
|
|
Agreed trying to do it electronically is going to take a lot of expensive development to get right.
If you take a look at the link from l0rd you'll see the tuners group version seems to be based around a cunningly designed rotating plate
arrangement, so could easily be a purely mechanical system.
But beyond the 'designed it myself' aspect I don't think it adds much to a road car. Sad really as sequential boxes are in
principle simpler in design than the H pattern ones, they just cost more as they are one-offs.
Maybe a DSG gearbox could be used instead of the UN1, Audi?
http://en.wikipedia.org/wiki/Direct-Shift_Gearbox
--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous
|
|
|
CNHSS1
|
| posted on 28/12/11 at 08:17 PM |
|
|
i have an Ikeya shifter for a nissan gearbox although have never yet used it.
pic of the Mitsi EVO version may give some inspiration. Basically a ratchet system which also moves left to right to give the effect of across DIY i
suspect.
http://www.ikeya-f.co.jp/en/car_type/mitsubishi/e-m-shifter-allparts.html
Most 'bike gear changes were based on a barrel design, as was if the rumours are true, the first sequential gearboxes Ford built for the WRC
Rallycars. Rumour was that various Yamaha bike box bits were cannabilised by M Sport up in Cumbria to produce the first WRC boxes for the focus
(IIRC).
if you zoom in on the pic of this Quaife type 9 sequential, you can see the barrel design
http://www.gearboxman.co.uk/psgearboxes.html
[Edited on 28/12/11 by CNHSS1]
"Racing is life, everything else, before or after, is just waiting"---Steve McQueen
|
|
|
v8kid
|
| posted on 28/12/11 at 08:49 PM |
|
|
quote:
Originally posted by iank
Agreed trying to do it electronically is going to take a lot of expensive development to get right.
I think electronically is a lot easier than mechanically! Every time you get a ramp angle wrong or miscalculate a spring k you have to remake the
parts. Also all the parts are custom instead of using off the shelf electronics components.
Further it looses the ability to link to the engine revs and speed sensor.
Consider coming up fast to a hairpin in 4th. You are braking like mad to get 90% of the braking done before the entry and then you have your hands
full with getting the car to the apex where you need second. Its busy in there and you don't quite get the engine at the right revs as you drop
it into second (having had to come through third first!). Bang round comes the back end and you are exiting backwards!.
Now with electronic selection all you do is brake, turn the wheel and dip the clutch when you are ready to accelerate. The wee processor takes care
of the gear selection and even knows the right revs for the engine so no more lock ups.
I really think the development of a mechanical system involves far more complex maths and fabrication skills than adjusting stepper motors with a
simple processor.
Cheers!
[Edited on 28-12-11 by v8kid]
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
|
|
|
iank
|
| posted on 28/12/11 at 09:38 PM |
|
|
quote:
Originally posted by v8kid
quote:
Originally posted by iank
Agreed trying to do it electronically is going to take a lot of expensive development to get right.
I think electronically is a lot easier than mechanically! Every time you get a ramp angle wrong or miscalculate a spring k you have to remake the
parts. Also all the parts are custom instead of using off the shelf electronics components.
Further it looses the ability to link to the engine revs and speed sensor.
Consider coming up fast to a hairpin in 4th. You are braking like mad to get 90% of the braking done before the entry and then you have your hands
full with getting the car to the apex where you need second. Its busy in there and you don't quite get the engine at the right revs as you drop
it into second (having had to come through third first!). Bang round comes the back end and you are exiting backwards!.
Now with electronic selection all you do is brake, turn the wheel and dip the clutch when you are ready to accelerate. The wee processor takes care
of the gear selection and even knows the right revs for the engine so no more lock ups.
I really think the development of a mechanical system involves far more complex maths and fabrication skills than adjusting stepper motors with a
simple processor.
Cheers!
[Edited on 28-12-11 by v8kid]
Designing electronic control systems for a living I'm quite sure it's possible, but I'll stick with lots of development and
road/track testing, and if/when you break a gearbox it's going get expensive - by the time you're done I'll bet it costs more than
going out and buying a quaife unless you can sell some to amortise the development.
My reasoning for mechanical over electronic (at least for diy attempts) is that the human brain is an awesome control system which take out a huge
amount of the complexity you'll end up with in an electronic solution, but the downside is it will be the same level of involvement as an H
pattern manual gearbox.
BUT if you manage to get it right it has the potential to be awesome and I'll be the first to applaud it.
One tip, stepper motors in my experience are either low torque and fast, medium torque and slow or high torque and really slow unless they are
physically large. Most high torque high speed applications go to a servo motor approach - which are even easier to drive from a microcontroller PWM
if you manage to find an integrated one you can use. Even with a stepper you'll need to have position feedback (or constantly recalibrate on
limit switches) as you'll lose steps now and again and hit problems when the accumulate.
--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous
|
|
|
v8kid
|
| posted on 28/12/11 at 10:10 PM |
|
|
Ta for input Iank although I don't fully agree with all your points.....
quote:
Originally posted by iank
Designing electronic control systems for a living I'm quite sure it's possible,Ooh! good can you do some of the design stuff on
programming them please? but I'll stick with lots of development and road/track testing, and if/when you break a gearbox it's
going get expensive - by the time you're done I'll bet it costs more than going out and buying a quaife unless you can sell some to
amortise the development.surely you are just as likely to break a box fiddling with the mechanicals?
My reasoning for mechanical over electronic (at least for diy attempts) is that the human brain is an awesome control system which take out a huge
amount of the complexity you'll end up with in an electronic solution, but the downside is it will be the same level of involvement as an H
pattern manual gearbox.Err what do you mean? Just leave as is?
BUT if you manage to get it right it has the potential to be awesome and I'll be the first to applaud it.I wouldn't mind some help
to do it actually 
One tip, stepper motors in my experience are either low torque and fast, medium torque and slow or high torque and really slow unless they are
physically large. Most high torque high speed applications go to a servo motor approach - which are even easier to drive from a microcontroller PWM
if you manage to find an integrated one you can use.Yup I agree but see my earlier post only 360 pulses per secons assuming that the shift is
completed in 1/4 sec. This is well within the stepper specs that I highlighted for £19 on ebay Even with a stepper you'll need to have
position feedback (or constantly recalibrate on limit switches) as you'll lose steps now and again and hit problems when the
accumulate.again agreed as i highlighted in first post how do they sense neutral as reference position?
Cheers!
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
|
|
|
MakeEverything
|
| posted on 29/12/11 at 12:47 AM |
|
|
quote:
Originally posted by v8kid
quote:
Originally posted by iank
Agreed trying to do it electronically is going to take a lot of expensive development to get right.
I think electronically is a lot easier than mechanically! Every time you get a ramp angle wrong or miscalculate a spring k you have to remake the
parts. Also all the parts are custom instead of using off the shelf electronics components.
Further it looses the ability to link to the engine revs and speed sensor.
Consider coming up fast to a hairpin in 4th. You are braking like mad to get 90% of the braking done before the entry and then you have your hands
full with getting the car to the apex where you need second. Its busy in there and you don't quite get the engine at the right revs as you drop
it into second (having had to come through third first!). Bang round comes the back end and you are exiting backwards!.
Now with electronic selection all you do is brake, turn the wheel and dip the clutch when you are ready to accelerate. The wee processor takes care
of the gear selection and even knows the right revs for the engine so no more lock ups.
I really think the development of a mechanical system involves far more complex maths and fabrication skills than adjusting stepper motors with a
simple processor.
Cheers!
[Edited on 28-12-11 by v8kid]
Ok, let me tell you what I do know.
I'm not building a track car, so won't be coming up to any hairpins fast in 4th, and hopefully won't ever need to get 90 percent of
braking in within 100m of the corner.
The original question (as reiterated) was does a sequential conversion exist for the UN1. Now, by virtue of my login name, you'll see that
I'm not scared of a bit of fabrication, so conversion was really the topic on the agenda.
I disagree with the electronics being simpler than mechanics on this occasion. Why on earth would I want engine speed sensors or intelligent gear
indicators, let alone paddle shifters or buttons? I did say that this wasn't what I wanted to achieve, and was just exploring the possibilities
of converting an h pattern UN1 to a sequential for the odd drag race I might want to participate in.
Thanks everyone for the input, it's a good discussion, but I'm still looking at what do I need to do to make the gears sequential? An
external ratchet system would appear to be quite slow and and possibly complex, as well as require some ignition cut switch to get into gear (flat
shift on MS). I'm starting to think that maybe i need to look inside and have dog cut (?) gears arranged sequentially internally??
Kindest Regards,
Richard.
...You can make it foolProof, but youll never make it Idiot Proof!...
|
|
|
hughpinder
|
| posted on 29/12/11 at 10:58 AM |
|
|
I was thinking of a conversion for mine. It helps that its a cable operated system on the mondeo box I have, as all you are looking for is to move 2
cables backwards and forwards. I was thinking of a cam type system pivoting round the gear lever pivot (one per cable obviously) to move the cable
back and forth ( a bit like the photo where its been converted to a horizontal plate that rotates), but since mines a midi, the 'tunnel'
is pretty empty and the rotating plates can be in the vertical axis which makes it simpler. You could have a third cam and some cheap switches to
indicate which gear you are in (I thought I'd at least have neutral and reverse).
Don't forget that in the end the gear lever just moves the dogs back and forth in the gearbox.
I have not got as far as deciding whether a ratchet or lock type mechanism would be required to stop the rotating plate rotating when you dont want it
to - I imagine something could be arranged like a spring loaded tapered pin that is released by the weight of your hand when you place it on the gear
lever.
As to the comments about 'imagine if you're approaching a corner.....' - well basically if you select the wrong gear you have a
problem - motorcyclist, including myself, have managed to cope with this for quite a while on motorbike sequential boxes where you may knock it down 2
or 3 gears at a time while braking.
Regards
Hugh
|
|
|
Paul Turner
|
| posted on 29/12/11 at 12:22 PM |
|
|
What happens if the system somehow fails and gets confused. If it downshifts instead of upshifting you could end up with a buzzed engine and a big
bill or if it downshifts the wrong number of gear into a corner you could end up exiting this life backwards. What happens if it cannot find a gear
when you are overtaking with a 42 tonner on your left and another coming strait for you.
|
|
|
hughpinder
|
| posted on 29/12/11 at 12:29 PM |
|
|
@paul turner- One of my friends had something similar to that when the gear lever came off in his hand during a slightly dodgy overtaking manouvre in
an audi quattro (standard H box). Having said that, I'd trust a mechanical system over electronics every day, and I've worked as an
automation engineer in chemical plants for the best part of 20 years! (Note criticals safety system will always have mechanical interlocking like the
castel keylock systems)
Regards
Hugh
|
|
|
scudderfish
|
| posted on 29/12/11 at 12:33 PM |
|
|
quote:
Originally posted by Paul Turner
What happens if it cannot find a gear when you are overtaking with a 42 tonner on your left and another coming strait for you.
Lift your right foot, move it a couple of inches to the left and press.
|
|
|
KFC
|
| posted on 2/7/12 at 08:04 PM |
|
|
Sequential bike gearbox
quote:
Originally posted by MakeEverything
Thanks for all the comments and support fellas, some good discussion.
The gears don't necessarily need t be h pattern, s was wondering if the shafts and gear arrange,ents could be modified to make them sequential
as well. Solenoid actuation is relatively fundamental, but the controller / PLC would need some thought.
Hey, you're after what I want.
I think it depends on how much work you want to do and how much of it you can do yourself?
I'm looking at a Hayabusa 1300 engine and breaking it down and selling the bits to fund the gearbox conversion, I'm unsure yet on how
much load the gearbox will take or I should go for another bike engine with a stronger gearbox.
I've seen enough photo's of inside of the box to have a go at making the gearbox conversion to fit a 3.5 V8 Rover engine. Lots of
fabricating and machining involved.
I know I'll get people saying, eh, why would you want to do that? Waste of time and effort.
Because it probably hasn't been done before??? A cheaper alternative to a proper dog ring box. I love the sequential dog ring gearbox, synchro
box is too slow.
I just want something a bit different.
Kev
[Edited on 2/7/12 by KFC]
|
|
|
v8kid
|
| posted on 2/7/12 at 10:51 PM |
|
|
Well I know that my original suggestion of doing this electronically did not go down well but......It need not be that bad.
More back of fag packet calcs and I think that a hobby servo motor would do it and still have nearly 100% power in reserve.
The key points are the motors cost under £20 each and they have all of the power electronics already inside them - and they can be easily modified to
give position feedback.
I found some programmes already written for Arduino controllers that are just about OK as they stand - the programme remembers positions and
regurgitates them on demand. See http://forums.trossenrobotics.com/tutorials/how-to-diy-128/get-position-feedback-from-a-standard-hobby-servo-3279/
It would still need two servos with a toothed belt drive and the servo time for each gearchange would be 0.12 sec per servo movement. 1 to 2 is .12
down to neutral plus another .12 down =2.4sec 2 to 3 is .12 up plus .12 across plus .12 up =.36sec etc...
Is that too slow do you think?
Can't see an easy way past reverse other than retaining the manual indent though.
So no collaboration then?
Cheers!
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
|
|
|
coyoteboy
|
| posted on 3/7/12 at 06:38 PM |
|
|
I've had this in the back of my mind for about 2 years now having developed a couple of similar systems (I develop prototype mechatronic
engineering solutions to order regularly). The problem I see is doing it using electromech actuators really doesn't seem elegant and while I
LOVE this sort of project I just don't see the point. You're just going to create a slow auto box because....it's not a dog box.
Half a second shift time is a lot slower than a human can do it with mechanical sympathy, without mech sympathy you're going to wear the box
FAST. Your typical bike box clutchless shift is coming in at ~100ms ish as far as I can see, that's slow. You could add in automatic mech
sympathy but then you're going to slow it back down again, so all you're really going to gain is the loss of a few push-pull cables and
about a £500 bill for electronics and actuators.
That's not to say don't do it. But I wouldn't do it how you're suggesting, if I did it at all.
I would tell you my plans but it's a potential earner so I'll not 
|
|
|
v8kid
|
| posted on 4/7/12 at 08:31 AM |
|
|
quote:
I would tell you my plans but it's a potential earner so I'll not
Go on, go on, go on ; you know you want to
I agree with your points however for me the issue is with reducing driver workload. If I can make it semi auto where all the driver has to is dip the
clutch when the change light comes on thats all I want. The idea is to map the arduino with preferred change rpm for each gear.
Also the mech system on the UN1 is slow no matter how good a shifter you are - the synchro cones just will not engage fastenough.
Further its a absolute bu66er to work out a change mech that is slick and easy to change gear with.
I know the hobby servo's are slow, in fact the times I quoted are no load times so it will be worse but its easy to get up and running with
it.
As a plus another student at the uni has some experience with programming them and is willing to help.
With my present workload I guess its a distraction but I reckon its a goer by Crimbo.
Cheers!
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
|
|
|
