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Suspension program - Vsusp

Posted: August 10, 2012, 5:20 pm
by andyawesome
just fiddling around while at work and found a simple online suspension analyzer, seems pretty interesting might be worth a look for some.... http://www.vsusp.com

and then some really rough playing around stuff

<a href="http://vsusp.com/index.pl?tool=2d#0.6&project_name:Locost1&front{frame.susp_type:0|frame.bottom_y:89|frame.center_to_upper_mount_x:305|frame.bottom_to_upper_mount_y:302|frame.center_to_lower_mount_x:218|frame.bottom_to_lower_mount_y:109|control_arms.upper_length:371|control_arms.lower_length:442|knuckles.hub_to_upper_x:122|knuckles.hub_to_lower_x:142|knuckles.hub_to_lower_y:89|knuckles.hub_to_upper_y:130|wheels.offset:46|wheels.diameter:14|wheels.diameter_expl:350|tires.size_convention:0|tires.section_width:185|tires.aspect_ratio:60|tires.diameter_expl:584|tires.width_expl:76}&rear{frame.susp_type:0|frame.bottom_y:102|frame.center_to_upper_mount_x:229|frame.bottom_to_upper_mount_y:254|frame.center_to_lower_mount_x:152|frame.bottom_to_lower_mount_y:79|control_arms.upper_length:333|control_arms.lower_length:445|knuckles.hub_to_upper_x:150|knuckles.hub_to_lower_x:114|knuckles.hub_to_lower_y:97|knuckles.hub_to_upper_y:122|wheels.offset:46|wheels.diameter:14|wheels.diameter_expl:350|tires.size_convention:0|tires.section_width:185|tires.aspect_ratio:55|tires.diameter_expl:500|tires.width_expl:76}" target="vsusp">Locost1</a>

Re: Suspension program

Posted: August 11, 2012, 10:47 am
by olrowdy_01
Pro: Looks pretty good. I'll have to play around with it some more to see how it compares with the results I ended up on my car.

Con: The program uses a mixture of mm and inches. I'd also like to see it allow manual input of the changes in chassis movement rather than the small dots you move around.

Personally I'd rather have the view point from the rear towards the front. But maybe some people are used to hanging on to the front of a car and looking back towards the rear while driving. :) :shock:

Re: Suspension program

Posted: August 11, 2012, 2:37 pm
by cheapracer
Looks like valuable fun, will investigate more tomorrow, spent a moment to say thanks at the bottom of the page ...

http://www.vsusp.com/?help=2d#what_is_vsusp

Re: Suspension program

Posted: August 11, 2012, 9:02 pm
by mattrogers
That looks pretty cool--It even has graphs as well. Whenever I get a chance, I'll plug in my real numbers to see how things line up in that program.

Re: Suspension program

Posted: August 11, 2012, 11:34 pm
by Rob7
Thanks, Cheapracer, for the message - much appreciated :D

Hey all,
If I can just jump in like this: I started writing VSusp several years ago when I was lurking on this forum and thinking about doing a Locost build. It wasn't quite the right time then, so I ended up forgetting about it until yesterday when I was showing my wife some Locost videos. She persuaded me to really buckle down and start a build. So I was surprised to see this thread pop up at the same time. Seems like a good omen to me :)

It's probably pretty obvious that Vsusp is still a work in progress (apologies for the rough edges). I've been wanting to update it for a while. I'm interested to hear if it could be of any use to you guys. And if you need some tweaks put in, I'll see what I can do!

Cheers,
Rob

Re: Suspension program

Posted: August 12, 2012, 4:09 am
by cheapracer
You're more than welcome Rob, hope I can help you in someway with your build in return for your generosity. :)

Re: Suspension program

Posted: August 12, 2012, 9:03 am
by Rob7
oops, duplicate post

Re: Suspension program

Posted: August 12, 2012, 12:47 pm
by Rob7
Thanks! I'm looking forward to helping out eventually. It may take a little while before I am well-acclamated, but I'll get there!

Cheers,
Rob

Re: Suspension program

Posted: August 12, 2012, 1:33 pm
by horizenjob
I've been wanting to update it for a while. I'm interested to hear if it could be of any use to you guys. And if you need some tweaks put in, I'll see what I can do!


Welcome to the forum, I hope we can inspire you to start a build.

I'm sure this can be of use to our builders. We don't really have standard suspensions yet so all our builders are faced with a good size learning curve and some decision making when it comes time to arming our builds with wheels that actually move up and down.

I'd like to offer links to setups with different parts in my threads and can imagine some more general threads on this too. It looks like a quick way to share part and geometry dimensions.

A couple of quick comments:
- The bump / droop numbers are said to be in mm, but seem to be inches?
- Maybe the front/rear suspension toggle should be included in the URL data?
- The sidebar takes up valuable room for the graph and suspension, perhaps it would work as well horizontally at the top of the page?

Re: Suspension program

Posted: August 12, 2012, 1:44 pm
by horizenjob
Another thing I have had trouble with is the way numbers are rounded. Sometimes it will take two decimal places and other times or places it won't. When you adjust the suspension by turning rod ends around you can get at least a minimal change of a half turn of a 20 threads per inch or 1/40 of an inch. So the program should allow hundreds of an inch anyway.

I'm trying to find things that might be easy to change but make a big practical difference.

Re: Suspension program - Vsusp

Posted: August 12, 2012, 3:23 pm
by Rob7
Thanks Horizenjob, I'll look into those suggestions tonight and try to get a new version up in a couple days or so

Re: Suspension program - Vsusp

Posted: August 12, 2012, 4:43 pm
by horizenjob
OK, I'm thinking:
1. Car9 + Vsusp
2. ???
3. World Domination!

I looked a little more to give you an example of the measurement issues. I'll describe it and I'm sure you'll know what's going on.

Here's a link to the config I was playing with. It is the rear suspension to MaxLessca's Locost with Ford IRS (Thunderbird parts).
http://tinyurl.com/LocostFordIRS

If you go to the rear suspension you see it has -0.7 degrees camber. If I adjust the upper link length by 1/10" I get 0 degrees camber. Then I take the URL and cut and paste it and get -0.1 degrees camber. The data in the URL is in millimeters and has been rounded in the URL. When it's converted back on the next visit it adds a decimal place, but I can't change that. People reasonably expect that the config they save and restore is the same afterwards, but it can vary by enough to notice.

I think this would work OK if the units you used were tenths ( or maybe hundredths ) of a millimeter. Then you don't need to worry about floating point arithmetic and the accuracy would be more then a tenth of a degree. I suggest hundredths or you'll still get the occasional question, there shouldn't be any problems with dynamic range.

Re: Suspension program - Vsusp

Posted: August 12, 2012, 5:02 pm
by olrowdy_01
I've used the trial version of Suspension Analyzer and in affect I am comparing Vsusp to that software.

Pro:
Vsusp looks like it will eventually be in that class of software. It will be very interesting to see how this software progresses.
The GUI, dimensioning displays and chart are very good.

Con:
When you make changes to the chart X data, the chart doesn't change unless you change one of the things you want graphed. I expected an "Enter" or "Redraw" button to appear after a change so the changes would be applied without changing a Y axis item. By having a button, if you don't click on the button the changes will be ignored and the original values would be used when you do something else.

There doesn't seem to be any way to input steering changes with resulting toe changes due to bump/droop/roll [yet?]. Maybe have a top view to display toe changes in 2d until the 3d version is done?

Re: Suspension program - Vsusp

Posted: August 13, 2012, 9:34 am
by Rob7
New version is up. This version includes small updates so I could refamiliarize myself with the code:
- moved navigation links to the top of the page (good call on that, Horizenjob)
- general layout cleanup, wider graph, bigger chart, generally less 1990s and more 2000s :)

Problems to work on next:
- vsusp is broken in IE7/8 and probably 9
- bump/droop units stuck in metric (thanks Olrowdy_01, Horizenjob)
- 1mm internal rounding bug (thanks Horizenjob)

Re: Suspension program - Vsusp

Posted: August 13, 2012, 9:40 am
by Rob7
horizenjob wrote:OK, I'm thinking:
1. Car9 + Vsusp
2. ???
3. World Domination!

I looked a little more to give you an example of the measurement issues. I'll describe it and I'm sure you'll know what's going on.

Here's a link to the config I was playing with. It is the rear suspension to MaxLessca's Locost with Ford IRS (Thunderbird parts).
http://tinyurl.com/LocostFordIRS

If you go to the rear suspension you see it has -0.7 degrees camber. If I adjust the upper link length by 1/10" I get 0 degrees camber. Then I take the URL and cut and paste it and get -0.1 degrees camber. The data in the URL is in millimeters and has been rounded in the URL. When it's converted back on the next visit it adds a decimal place, but I can't change that. People reasonably expect that the config they save and restore is the same afterwards, but it can vary by enough to notice.

I think this would work OK if the units you used were tenths ( or maybe hundredths ) of a millimeter. Then you don't need to worry about floating point arithmetic and the accuracy would be more then a tenth of a degree. I suggest hundredths or you'll still get the occasional question, there shouldn't be any problems with dynamic range.

I took a couple minutes to check out your Car9 project. Wow, quite a lot of information in there. Is Car9 a database of all the Locost frame and suspension info available? Maybe I can plug some of your data into Vsusp somehow. Definitely something to think about