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Hey nice chasis, I like the underside shot where you can see all the steered
wheels. Hmmm, what are your thoughts on the strength of the center of the
chasis? Looks like some more latice work will come in to play when you keep
building to keep it squared up.
Thoughts?
e
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In lugnet.technic, Eric Sophie wrote:
> Hey nice chasis, I like the underside shot where you can see all the steered
> wheels.
For a while now I've been wanting to build a vehicle with multiple evenly spaced
steered axles. The difference this time being that instead of using gearing to
generate the different steering angles required I'd like to use fixed links
instead. My problem is that despite looking on the internet I can't find the
right equations to work out the lengths of the links.
I can work out how much each axle should steer to accurately track around a
single point of rotation, but it's the second part of the maths that elude me.
Does any one know how to do this?
I reckon I'll probably have to use Lego screw threads to get the precise link
length I need, but that shouldn't be too much of a problem.
The chassis will form the first (fixed) link. Each of the two axles I'm
connecting will have it's own steering arm at a ninety degree offset, and then
the final link will connect them.
As each successive axle will turn less, the system will effectively be geared
down as it goes along, requiring less additional energy each time an axle is
added.
Steve
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This model incorporates geared steering (I don't need to tell you how difficult
it is to turn the darn thing! If you are to build something as complex and big
as this, DO NOT go for geared steering.
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In lugnet.technic, Eric Sophie wrote:
> Hey nice chasis, I like the underside shot where you can see all the steered
> wheels. Hmmm, what are your thoughts on the strength of the center of the
> chasis? Looks like some more latice work will come in to play when you keep
> building to keep it squared up.
>
> Thoughts?
>
> e
Earlier today I started on the driver's cab (again using the cab of the set 8421
as a base, I was able to modify it, ie give it doors that open and close). It
didn't take too much time, but what was a real problem was the pins. After
pushing them in and pulling them out, after a while it really hurts the thumbs
(well mine anyway). Pics of the cab will be up shortly.
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In lugnet.technic, Vineet Honkan wrote:
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In lugnet.technic, Eric Sophie wrote:
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Hey nice chasis, I like the underside shot where you can see all the steered
wheels. Hmmm, what are your thoughts on the strength of the center of the
chasis? Looks like some more latice work will come in to play when you keep
building to keep it squared up.
Thoughts?
e
|
Earlier today I started on the drivers cab (again using the cab of the set
8421 as a base, I was able to modify it, ie give it doors that open and
close). It didnt take too much time, but what was a real problem was the
pins. After pushing them in and pulling them out, after a while it really
hurts the thumbs (well mine anyway). Pics of the cab will be up shortly.
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Your Hands Need a Spa!
wow, from 3 years ago
e
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In lugnet.technic, Eric Sophie wrote:
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In lugnet.technic, Vineet Honkan wrote:
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In lugnet.technic, Eric Sophie wrote:
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Hey nice chasis, I like the underside shot where you can see all the
steered wheels. Hmmm, what are your thoughts on the strength of the center
of the chasis? Looks like some more latice work will come in to play when
you keep building to keep it squared up.
Thoughts?
e
|
Earlier today I started on the drivers cab (again using the cab of the set
8421 as a base, I was able to modify it, ie give it doors that open and
close). It didnt take too much time, but what was a real problem was the
pins. After pushing them in and pulling them out, after a while it really
hurts the thumbs (well mine anyway). Pics of the cab will be up shortly.
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Your Hands Need a Spa!
wow, from 3 years ago
e
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On a related note, I stubbed my toe quite badly yesterday, in very close
proximity to some Meccano. Its still throbbing now.
Steve
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In lugnet.technic, Steve Lane wrote:
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In lugnet.technic, Eric Sophie wrote:
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Hey nice chasis, I like the underside shot where you can see all the steered
wheels.
|
For a while now Ive been wanting to build a vehicle with multiple evenly
spaced steered axles. The difference this time being that instead of using
gearing to generate the different steering angles required Id like to use
fixed links instead. My problem is that despite looking on the internet I
cant find the right equations to work out the lengths of the links.
I can work out how much each axle should steer to accurately track around a
single point of rotation, but its the second part of the maths that elude me.
Does any one know how to do this?
I reckon Ill probably have to use Lego screw threads to get the precise link
length I need, but that shouldnt be too much of a problem.
The chassis will form the first (fixed) link. Each of the two axles Im
connecting will have its own steering arm at a ninety degree offset, and then
the final link will connect them.
As each successive axle will turn less, the system will effectively be geared
down as it goes along, requiring less additional energy each time an axle is
added.
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Well I didnt bother working out the exact lengths, but I found
this technique works ok.
Ive since refined it to allow normal steering and crab steering, and anything
in between, but have yet to actually complete a MOC using it.
ROSCO
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In lugnet.technic, Ross Crawford wrote:
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Well I didnt bother working out the exact lengths, but I found
this technique works
ok. Ive since refined it to allow normal steering and crab steering, and
anything in between, but have yet to actually complete a MOC using it.
ROSCO
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That wouldnt work with my design as there is very little room in the middle.
Id intended to link the opposing wheels with just a normal bar. The linkages
between axles are going to run down just the left (or right) side.
Steve
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In lugnet.technic, Vineet Honkan wrote:
> I just reorganised my picture folders. Here is the new folder, with pics of the
> cab. Enjoy!
>
> http://www.brickshelf.com/cgi-bin/gallery.cgi?f=141997
Good progress! If I made progress like that, perhaps my Mana Cat would be
further along than it is now.
:(
e
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Is it a lot easier to turn than using gears? Also, is it possible to hook this
system up to a steering wheel?
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In lugnet.technic, Steve Lane wrote:
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In lugnet.technic, Ross Crawford wrote:
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Well I didnt bother working out the exact lengths, but I found
this technique works
ok. Ive since refined it to allow normal steering and crab steering, and
anything in between, but have yet to actually complete a MOC using it.
|
That wouldnt work with my design as there is very little room in the middle.
Id intended to link the opposing wheels with just a normal bar. The linkages
between axles are going to run down just the left (or right) side.
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There is no requirement to have the main linkage down the centre, although that
does simplify it somewhat. Those pics are only the basic prototype of the idea
;)
ROSCO
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In lugnet.technic, Vineet Honkan wrote:
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Is it a lot easier to turn than using gears? Also, is it possible to hook
this system up to a steering wheel?
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I drive the steering via a linkage to the very end of the main drive beam.
ROSCO
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