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My own upright

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Priyank View Drop Down
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    Posted: Aug/10/2012 at 9:56pm
Hey everyone.
I want to design my own uprights this time
Nit because A i can't get it pre fabricated, which i can, but i just want to understand how exactly it is designed out, not by software FEA, but by simple FBD and machine design.

I have figured out the 5 primary forces acting, but i can't seem to understand how the stresses are developed in the upright.
As in, when it acts like a beam, when like a member under tension, when like a strut etc.
These days, softwares do everything but i want to design by my own hand.
Any insights ??
I have searched the entire forum and WWW, got nothing.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Aug/11/2012 at 12:24am
What loads did you identify and what basic shape are you going for?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Priyank Quote  Post ReplyReply Direct Link To This Post Posted: Aug/11/2012 at 8:45pm
I considered the forces on all 3 axes, weight, lateral forces and accelerative and braking forces.
I analysed the directions about which they ac t, and the effect they have on the upright.

My question is how to take an optimal shape ?

My shape is simple...
A filleted rectangle with a hole in middle for the bearing 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Aug/11/2012 at 8:58pm
There isn't an optimal shape, that is the beauty of actual design work! Determine where things need to go, figure out your joints, think on your own how to connect everything. Don't bother looking for equations or asking how to connect the dots, that is for you to decide. The computer will not do it for you! Later on refer to equations and FBD to scale your designs to handle the load.

There is nothing wrong with a rectangle.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Priyank Quote  Post ReplyReply Direct Link To This Post Posted: Aug/11/2012 at 9:05pm
Alright, but I'm not much satisfied.
I did the stress analysis, and found out that i have corners where i can cut.
Have you ever made an upright before ?
Could we have a discussion on that ?
I might like to elaborate how i started designing.
Maybe you could correct me somewhere. 
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Post Options Post Options   Thanks (2) Thanks(2)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Aug/11/2012 at 9:37pm
Yes I've made an upright before and its just like EVERY other part on the vehicle. It starts something like this: 
We need X to do Y+W+Z and maybe P & T.
Walk over to the chalkboard. 
Imagineer starts drawing different ideas but only for a little amount of time (don't lose focus on what is necessary!!)
Imagineer goes to class, gets board in class, and keeps drawing ideas on class notebook.
Imagineer narrows down design concepts and focuses on Ideas A,B,C
Idea A gets thrown in the trash because it is a PITA to manufacture/costly
Idea B does  W and Z really well but design C does Y,P, and T really well
Go back to class, Fail exam. But more importantly a design idea comes into mind during the exam
Back to the chalkboard, compromise designs B and C into new idea D.
Go to computer, make 3d model of idea D
Do engineering, scale components properly.
Celebratory Beer.
Remember driver is idiot, scale bigger.
Skip class, machine, hammer, weld sh*t.
Assemble design D.
Realize components were invisible during the CAD packaging check.
Find BFH, Use BFH. Make Fit.
Fail class, stay in college forever, weld more sh*t.

Every design project I've been involved in goes something like this.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote PrestonGable Quote  Post ReplyReply Direct Link To This Post Posted: Aug/11/2012 at 10:16pm
Story of my life. Except with more profanity and a angry girlfriend.

Find pictures of what other people have done. Don't copy them but look at what they did and try to understand why. There are a million different way of doing something and thousands of ways of making it work. There is no perfect design. Also never forget that at the end of the day you still have to manufacture the thing. You are on the right track by not jumping straight into FEA and don't until you understand your FBD. Also never forget a healthy factor of safety.


Edited by PrestonGable - Aug/11/2012 at 10:21pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Priyank Quote  Post ReplyReply Direct Link To This Post Posted: Aug/12/2012 at 11:41am
Erikhardy, 
About your post :

CTRL C
CTRL V (MS Word)
CTRL S
Archived !!


Preston:
I was looking for a more technical thing, but i guess this is much more important than that Tongue

I am a person who is not much into softwares, even till the extent that i dislike using them for design purposes.

I guess I have done all that, and now my perfect upright (LOL) is ready.
Posting design in a few hours :)


Edited by Priyank - Aug/12/2012 at 11:42am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote zglazer Quote  Post ReplyReply Direct Link To This Post Posted: Aug/12/2012 at 12:06pm
Originally posted by Priyank Priyank wrote:

I am a person who is not much into softwares, even till the extent that i dislike using them for design purposes.
The worst tool is the one you refuse to use. The reason software exists is because it can do things much more quickly than you can do them by hand, and it can do things you can't do by hand at all. While it's important to understand the principles behind what you're doing before you start playing with software, you shouldn't ignore its usefulness either.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Priyank Quote  Post ReplyReply Direct Link To This Post Posted: Aug/12/2012 at 12:11pm
I understand that, but it's about personal interest.
I find stuff done by hand more reliable, not in terms of numerical values, but by common sense.

As Erik pointed out, things begin from chalkboard, and end there too.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote zglazer Quote  Post ReplyReply Direct Link To This Post Posted: Aug/12/2012 at 12:23pm
Originally posted by Priyank Priyank wrote:

I understand that, but it's about personal interest.
I find stuff done by hand more reliable, not in terms of numerical values, but by common sense.
That argument simply does not make sense. If the numbers aren't reliable, the analysis is meaningless.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote collinskl1 Quote  Post ReplyReply Direct Link To This Post Posted: Aug/12/2012 at 1:15pm
Good luck in industry man... while pencils, paper, and hand calcs are still used daily by everyone, you'll be crippled without knowing how or wanting to use the engineering tools of the day i.e. computers.
 
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote PrestonGable Quote  Post ReplyReply Direct Link To This Post Posted: Aug/12/2012 at 4:59pm
I was not trying to say that using the computer is not important or not essential. Its important when starting out to think things through. But after you have done that and figured out what you wish to do, you have to realize the the finite design and analysis is going to need to occur on the computer, and then backed up by hand calcs and common sense. Not utilizing all the tools at your disposal is a terrible mistake to make. My point was to not jump into the computer right away and get lost in there with some impractical design that could never be built.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote collinskl1 Quote  Post ReplyReply Direct Link To This Post Posted: Aug/12/2012 at 5:15pm
Preston, my comments were not directed at you.  I couldn't agree more with what you just said.  I've ranted about meaningless FEA results on here before Smile
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Post Options Post Options   Thanks (0) Thanks(0)   Quote PrestonGable Quote  Post ReplyReply Direct Link To This Post Posted: Aug/12/2012 at 5:26pm
No problem just reread my post and wanted to add that fact in you have to at some point use the computer to do your finite design and analysis. But I've seen to many people run to it as there first step and get stuck in Lala computer land for the next month or so and turn out junk. Then I end up just making something else in the shop out of some thick material i don't think will break that works.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote taukea Quote  Post ReplyReply Direct Link To This Post Posted: Aug/13/2012 at 8:48am
Originally posted by PrestonGable PrestonGable wrote:

No problem just reread my post and wanted to add that fact in you have to at some point use the computer to do your finite design and analysis. But I've seen to many people run to it as there first step and get stuck in Lala computer land for the next month or so and turn out junk. Then I end up just making something else in the shop out of some thick material i don't think will break that works.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote ktb_919 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/17/2012 at 12:32pm
I see that I'm a little late to the party, but I thought I'd throw in my two cents.
 
Last year we re-designed custom uprights after XXX years of using the same ones.  The first thing I did was get a hold of an in-production atv upright.  That helped get the creative juices flowing, plus at least you have something to take measurements off of.  Getting that basic shape made it much easier to add in the mounting points to the rest of the suspension/brake system and then to carve out the final design. 
 
Something we didn't really take into consideration was manufacturing.  We knew we wanted to use a CNC mill, but we didn't think about how the machine would cut our part or how long it would take.  It ended up taking about 4 hours to machine just one upright from billet!  Needless to say, we won't be removing as much material this year.  It's up to you to decide whether its worth waiting an extra hour to shave off a little bit of weight.
 
Another thing that tripped us up:  Make sure you take measurements of the exact hub bearings you will be using.  We had to remake our spindles because we failed to do that.   
 
Here's some pics of the models from our design if you or anyone else is interested:
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Priyank Quote  Post ReplyReply Direct Link To This Post Posted: Sep/17/2012 at 12:37pm
Did this work well ??
What material ??
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ktb_919 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/17/2012 at 10:24pm
We didn't have any problems at all this year which is fantastic because we used to have upright related failures all the time.  We machined these from 6061-T6 aluminum billet, 4130 steel for the spindles
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2012 at 12:21am
Our design looked fairly similar except fully boxed / gusseted with the lower a arm pivot and steering knuckle in double shear and the knuckle in the front and caliper behind the kingpin axis. Our upright and spindle were both aluminum.

From my experience, 4 hours on a CNC to save a couple tenths of a pound is definitely worth it (as long as it isn't during the pre-competition final rush).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2012 at 12:27am
In case what I wrote was confusing, here is a picture from testing before polishing.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2012 at 7:11am
Danny, can you turn the steering wheel with the push of a breathe with that much spindle offset?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote zmpeck Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2012 at 8:41am

Here's a picture of MTU's front knuckles, using rod ends in bending(gasp).  The misalignment spacers allow for 40* of steering, and we use removeable steering arms & caliper mounts so the upright can be used on both sides of the car.

 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/18/2012 at 10:08am
That is the idea. The steering in last year's car was nice and light with a pretty fast ratio but it wouldn't kick you around in ruts too badly. Otto can elaborate on them much better if you have any specific design questions.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Vladmir123 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/20/2012 at 11:21am
Originally posted by Soccerdan7 Soccerdan7 wrote:

In case what I wrote was confusing, here is a picture from testing before polishing.



You guys have achieved caster here by inclining your whole knuckle along the line of caster, but in your 2012 vehicle you guys have done it by offsetting your ball joint positions.
   Does this affect your camber/caster gain differently? Or does it affect any parameter differently at all?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/20/2012 at 11:41am
If I understand what you are asking, it is simply a question of geometry, stress and machinability. Only the locations of the pivots matter for vehicle dynamics, not the material that connects them.

The 2008 and 2012 geometry is very different though in terms of caster, kingpin inclination and steering geometry, so comparing the uprights does not make a lot of sense.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote abhinav.chiku Quote  Post ReplyReply Direct Link To This Post Posted: Oct/10/2012 at 10:54am
Originally posted by Soccerdan7 Soccerdan7 wrote:

In case what I wrote was confusing, here is a picture from testing before polishing.


In this type of knuckle, i.e. keeping the steering axis a little far off the centre of the wheel,wont this affect the camber gain in turns or while steering,also wont it increase the steering effort,though i think it might be compensated by the reduction in the mechanical trail-which also helps in keeping the vehicle moving in straight line ahead.

I was actually trying to implement this kind of design(keeping the mount points sidewards,such that the steering axis is far away from the wheel centre towards the rear)so that i can get extra space for keeping the arms longer than they are.
So can you please help me with the Pros and cons for this .

Thank You
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Post Options Post Options   Thanks (0) Thanks(0)   Quote abhinav.chiku Quote  Post ReplyReply Direct Link To This Post Posted: Oct/10/2012 at 10:59am
Also i wanted to keep a high caster angle to keep intentional camber gain while steering and especially cornering,So would the design above mentioned would be a problem for that.
P.S. :- our caster angle is 15 degrees
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/10/2012 at 11:24am
Originally posted by abhinav.chiku abhinav.chiku wrote:

In this type of knuckle, i.e. keeping the steering axis a little far off the centre of the wheel,wont this affect the camber gain in turns or while steering,also wont it increase the steering effort,though i think it might be compensated by the reduction in the mechanical trail-which also helps in keeping the vehicle moving in straight line ahead.

I was actually trying to implement this kind of design(keeping the mount points sidewards,such that the steering axis is far away from the wheel centre towards the rear)so that i can get extra space for keeping the arms longer than they are.
So can you please help me with the Pros and cons for this .

Thank You

Having the steering knuckle far from the kingpin axis decreases your steering effort. Also, you have to keep in mind we have a decently high castor angle, so the whole upright is reclined with respect to the vertical. We don't have too much mechanical trail, so the wheel does kick around a little through the rough stuff but it hasn't been a problem for us.

Your camber gain in steer is controlled only by your kingpin axis. Once you choose the endpoints and have thereby set your caster and kpi, you know the behavior in steer. The location of the knuckle only changes steering effort, travel, ackerman and packaging. This location depends a lot on your steering rack ratio, location and desired steering angles at the wheel and at the steering wheel.

I am not sure what you mean about keeping the knuckle far away to keep your "arms longer." Be careful about snapping your knuckle off in a harsh landing or from fatigue. Steering stops are your friend.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote abhinav.chiku Quote  Post ReplyReply Direct Link To This Post Posted: Oct/10/2012 at 2:41pm
Originally posted by Soccerdan7 Soccerdan7 wrote:



Having the steering knuckle far from the kingpin axis decreases your steering effort. Also, you have to keep in mind we have a decently high castor angle, so the whole upright is reclined with respect to the vertical. We don't have too much mechanical trail, so the wheel does kick around a little through the rough stuff but it hasn't been a problem for us.

Your camber gain in steer is controlled only by your kingpin axis. Once you choose the endpoints and have thereby set your caster and kpi, you know the behavior in steer. The location of the knuckle only changes steering effort, travel, ackerman and packaging. This location depends a lot on your steering rack ratio, location and desired steering angles at the wheel and at the steering wheel.

I am not sure what you mean about keeping the knuckle far away to keep your "arms longer." Be careful about snapping your knuckle off in a harsh landing or from fatigue. Steering stops are your friend.


Actually by knuckle I meant Upright.Sorry its called knuckle in my college.Anyway thanks for your reply,was quite informative.
But what i wanted to ask was in upright design if i keep the kingpin axis away from the centre of the wheel like the one in the above
image(kingpin axis not passing through wheel centre in side view andd instead far away from it   ) what consequences will it have on the : -
1. Camber Gain during steering and cornering.
2. We also run a high caster for this intended camber gain at corners.
3. What effect will the kingpin axis offset from wheel centre have on the steering effort.
And about the arms-what i want to say is that by placing the mounting points on the side of the upright like you have done we will get extra space in the front view to extend the arms by an inch or two.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Soccerdan7 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/10/2012 at 2:50pm
Originally posted by abhinav.chiku abhinav.chiku wrote:


Actually by knuckle I meant Upright.Sorry its called knuckle in my college.Anyway thanks for your reply,was quite informative.
But what i wanted to ask was in upright design if i keep the kingpin axis away from the centre of the wheel like the one in the above
image(kingpin axis not passing through wheel centre in side view andd instead far away from it   ) what consequences will it have on the : -
1. Camber Gain during steering and cornering.
2. We also run a high caster for this intended camber gain at corners.
3. What effect will the kingpin axis offset from wheel centre have on the steering effort.
And about the arms-what i want to say is that by placing the mounting points on the side of the upright like you have done we will get extra space in the front view to extend the arms by an inch or two.

The offset of the kingpin axis behind the wheel center isn't the important thing, but you are likely to end up with something similar based on what you want. Based on caster and mechanical trail requirements, you are kind of forced into this position.

This offset doesn't determine your effort or camber change, as it is the caster and trail that individually effect these things. The farther the point about which the wheel is trying to turn is from the center of your contact patch, the more steering effort you are going to have. High caster angle with low mechanical trail will still be fairly low effort steering but will push the kingpin axis back and at an angle like ours.

All of this is independent of your steering arm / knuckle / tie rod location. What matters there is the distance to the kingpin axis. Other positional changes will change ackerman some and may vary your max steering angle depending on when spherical bearings or rod ends bind.

Basically, I am saying if you pick parameters correctly, you can get what you want with minimal downsides that you are worried about.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote otto Quote  Post ReplyReply Direct Link To This Post Posted: Oct/10/2012 at 8:19pm
As danny said, its a matter of knowing what you want specifically.  The two important things are perpendicular distance between the steering axis and the tie rod mount and the steering axis offsets from the contact patch.  Packaging will dictate how closely you are able to achieve your desired parameters (caster, mechanical trail, scrub, kingpin inclination).  Here I am using steering axis to mean the line connecting the upper and lower ball joints for a dual-A arm setup (AKA kingpin axis).  The rotation axis for the wheel does not need to be in line with the steering axis.  For some reason a lot of people seem to think that is a geometric requirement.  If you have a setup where you don't have a live spindle (or have a stub axle) you get a good amount of flexibility on where to locate the wheel rotation axis in the side view plane.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nihal Quote  Post ReplyReply Direct Link To This Post Posted: Mar/28/2013 at 6:27am
I read the above discussion and got to know that more castor angle leads to 
more camber gain while cornering. Does any one know the exact relation between castor angle and camber gain. I mean some sort of formula..
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/28/2013 at 11:05am

A simple 3D Geometry analysis will show you that the camber variation in steering is

= KPI Angle x (1-cos(Steering angle))- Caster angle x Sin (steering angle)

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Post Options Post Options   Thanks (0) Thanks(0)   Quote nihal Quote  Post ReplyReply Direct Link To This Post Posted: May/24/2013 at 11:32am
hello everyone. 
thanks for your formula Akron..
But I am facing a little bit of problem. When I plugged in the formulas in excel sheet, I am getting
camber change as negative for both the outer and inner wheels 

I kept kingpin as 0 and castor as 8 degrees. I entered steering angle values as positive magnitudes for both the inner and outer wheel. Correct me if I made a mistake in filling in the datas. I mean positive or negative signs for angle. According to my knowledge I should get positive camber change for inner wheel and negative camber change for outer wheel for positive castor and 0 kingpin. I am getting confused. 

Please throw some light... 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: May/24/2013 at 12:22pm
Both wheels would lean into the turn.
I believe your issue is the inside wheel steering angle is positive and the outside wheel steering angle is negative for the equation.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nihal Quote  Post ReplyReply Direct Link To This Post Posted: May/24/2013 at 1:36pm
@ Arkon

i should be but its coming negative for both the wheels if i enter the steering angles as positive. 
For example, 15 degree for inner wheel and 7 degree for outer.

That is why I am getting confused whether the eqn should be modified or I am entering wrong sign for steering angles.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nihal Quote  Post ReplyReply Direct Link To This Post Posted: Jun/12/2013 at 9:21am
Originally posted by ktb_919 ktb_919 wrote:

I see that I'm a little late to the party, but I thought I'd throw in my two cents.
 
Last year we re-designed custom uprights after XXX years of using the same ones.  The first thing I did was get a hold of an in-production atv upright.  That helped get the creative juices flowing, plus at least you have something to take measurements off of.  Getting that basic shape made it much easier to add in the mounting points to the rest of the suspension/brake system and then to carve out the final design. 
 
Something we didn't really take into consideration was manufacturing.  We knew we wanted to use a CNC mill, but we didn't think about how the machine would cut our part or how long it would take.  It ended up taking about 4 hours to machine just one upright from billet!  Needless to say, we won't be removing as much material this year.  It's up to you to decide whether its worth waiting an extra hour to shave off a little bit of weight.
 
Another thing that tripped us up:  Make sure you take measurements of the exact hub bearings you will be using.  We had to remake our spindles because we failed to do that.   
 
Here's some pics of the models from our design if you or anyone else is interested:
 




I am considering aluminium hubs with steel spindle. But I am not sure how to join them? I have an idea of press fitting and bolting them but not quiet sure about it? Can you tell me how you guys attach the steel spindle to the aluminium upright.. It would be of great help. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote paasch Quote  Post ReplyReply Direct Link To This Post Posted: Jun/12/2013 at 11:26am
Originally posted by nihal nihal wrote:

 
I am considering aluminium hubs with steel spindle. But I am not sure how to join them? I have an idea of press fitting and bolting them but not quiet sure about it? Can you tell me how you guys attach the steel spindle to the aluminium upright.. It would be of great help. 

Press fit.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Yaseen Quote  Post ReplyReply Direct Link To This Post Posted: Sep/04/2013 at 3:19pm
We are planning to do an offset steering axis in the front upright. Which point must be taken as the "spindle point".?? Need those co-ordinates for lotus. is it X or Y?

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Post Options Post Options   Thanks (0) Thanks(0)   Quote otto Quote  Post ReplyReply Direct Link To This Post Posted: Sep/04/2013 at 8:12pm
if this is for figuring out leverage on the steering assembly, it would be the axis going through Y

your toe link mounting point is not shown.

if this is for loads coming from the wheel, they will act about the moment arm defined by XY
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Post Options Post Options   Thanks (0) Thanks(0)   Quote anu1097 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/28/2014 at 7:29am
can anyone of you please show some images of Wheel upright made by 3 axis CNC
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Chirayu Quote  Post ReplyReply Direct Link To This Post Posted: Jul/22/2014 at 4:04pm
I am trying to design my own steering knuckle for BAJA SAE 2015 (India). I cannot identify the forces acting on the knuckle. Can someone please list the forces and the respective directions in which they act. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote zglazer Quote  Post ReplyReply Direct Link To This Post Posted: Jul/22/2014 at 4:11pm

If you're not able to draw a free-body diagram of an upright, I find it very unlikely that you will be able to design one. Keep trying to identify the forces until you're actually able to do it. Then you can start worrying about your upright design.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote anu1097 Quote  Post ReplyReply Direct Link To This Post Posted: Jul/22/2014 at 4:33pm
could somebody please help me in the simulation of upright in solidworks.
I have done simulstions for cornering forces. But when I was trying to do simulation for braking torque I was not able to apply torque. Can somebody provide a link to help me or just guide me.
Thank You
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Big_Mac93 Quote  Post ReplyReply Direct Link To This Post Posted: Jul/23/2014 at 8:05am
anu, I might not be correct about this since I have only done a little bit of simulation in solidworks but torque = force*radius so depending on exactly what you are trying to simulate you could make an assumption about the location and size of your force from the center of your rotor, put that into solidworks and that would be your torque.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sujandinesh Quote  Post ReplyReply Direct Link To This Post Posted: Jul/23/2014 at 8:51am
Can you elaborate on the problem? What are the errors that you're getting?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RLM Quote  Post ReplyReply Direct Link To This Post Posted: Jul/23/2014 at 12:05pm
for brake torque, when your applying the force, click on the surfaces that will be transfering the force from the caliper to the upright (likely your bolts). this will cause there to be little pink circular arrows in the holes. now select around common axis (I cant remember exactly what the button is called but can look at it later today). select the axis that the wheel is spinning about ( spindle axis) and volia brake torque. now input your force that your brakes apply ( F=T/D) and run your simulation. 

Hope this helps

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Post Options Post Options   Thanks (0) Thanks(0)   Quote sasikumarveluchamy Quote  Post ReplyReply Direct Link To This Post Posted: Jul/29/2015 at 1:56pm
Originally posted by Soccerdan7 Soccerdan7 wrote:

In case what I wrote was confusing, here is a picture from testing before polishing.
uploads/473/396460_10150481052565286_895736632_n.jpg


Meanwhile, What is the material used for the hub in this image ? Nylon kind of stuff ?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote kcooper273 Quote  Post ReplyReply Direct Link To This Post Posted: Jul/29/2015 at 4:20pm
Originally posted by sasikumarveluchamy sasikumarveluchamy wrote:

Originally posted by Soccerdan7 Soccerdan7 wrote:

In case what I wrote was confusing, here is a picture from testing before polishing.
uploads/473/396460_10150481052565286_895736632_n.jpg


Meanwhile, What is the material used for the hub in this image ? Nylon kind of stuff ?

Yes that is definitely nylon.
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