DMac's F1000 Build

I know that many of you have been asking about my F1000 design, so I finally decided to start a thread for it. Right now, I have designed the frame on SolidWorks and performed simulated testing on it. Attached are images of the frame and simulation images.

My target date for completion is January 2011, just in time for those early season races. *knocks on wood*

Once I get back to school and SolidWorks, I continue on this project in earnest.

Plans from here:
Insert GSXR cad model and work on motor mounts
Add front suspension mounting points to frame and design front suspension
Insert "stock" parts into assembly - wheels, brakes, steering wheel
Design rear suspension and suspension/differential/wing mount assembly
Design an initial body and wings
CFD CFD CFD CFD...
Check everything over a.k.a. GCR compliance
Build it

Shouldn't be bad at all, eh? ;)

Excellent. Welcome. Best of luck. Look forward to watching your progress. I think you'll find plenty of help and support here.

Looks like a neat project with good design progress.

Recommendations;
- Check the GCR for rollhoops requirements before moving along much further

- Don't forget that the bottom of the chassis can be riveted and bonded shear panels. You might not have the need for as many tubes on the bottom.

- Think ahead about spring/damper mounts integrated into the chassis, as well as bell crank location.

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Originally Posted by RobLav

Looks like a neat project with good design progress.

Recommendations;
- Check the GCR for rollhoops requirements before moving along much further

- Don't forget that the bottom of the chassis can be riveted and bonded shear panels. You might not have the need for as many tubes on the bottom.

- Think ahead about spring/damper mounts integrated into the chassis, as well as bell crank location.

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I looked at the GCR while I was building it, but I will definitely go back and check it. Much better to fix it now while I am still working in pixels.

This was my first pass at building just a frame. Once I get back to SolidWorks, I'll start adding mount points, etc.

Quote:

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Originally Posted by RobLav

- Don't forget that the bottom of the chassis can be riveted and bonded shear panels. You might not have the need for as many tubes on the bottom.

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For that same reason, you should consider square tube for the bottom rails to give more bonding surface.

D Mac,

You're off to good start. Keep the updates coming.

Have you looked into your suspension upright design yet? I would be willing to bet there are a few guys watching this thread that have some great parts available for your application. You may want to look into sourcing a variety of parts to tie your geometry together. From a person that has built a couple of cars from scratch, you will need to start cutting metal in the next couple of months to meet your completion date.

Good luck and welcome to the F 1000 ranks. :thumbsup:

I am fairly new to Simulation and Flow Simulation, so it's not obvious to me what you are using for your fixture points, and where you are applying your forces and their resulting vectors.

Also, what factor of safety are you designing for? I'm guessing the material you are using is 4130?

If anyone wants to post a primer on how to correctly analyze a chassis for crash-worthiness and for rigidity when seeing loads through suspension pickups, I am sure that there would be a few of us quite interested.

Also, what environment are you running in? I am trying to do some external CFD in 3D with WinXP x32, however, I receive errors about not having enough continuous free memory, so I can only solve a 2D domain. I will be upgrading to windows 7 x64 tonight in order to take advantage of my processors and additional memory. Any advice on this front?

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Originally Posted by na94

I am fairly new to Simulation and Flow Simulation, so it's not obvious to me what you are using for your fixture points, and where you are applying your forces and their resulting vectors.

Also, what factor of safety are you designing for? I'm guessing the material you are using is 4130?

If anyone wants to post a primer on how to correctly analyze a chassis for crash-worthiness and for rigidity when seeing loads through suspension pickups, I am sure that there would be a few of us quite interested.

Also, what environment are you running in? I am trying to do some external CFD in 3D with WinXP x32, however, I receive errors about not having enough continuous free memory, so I can only solve a 2D domain. I will be upgrading to windows 7 x64 tonight in order to take advantage of my processors and additional memory. Any advice on this front?

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In the simulation pictures, the purple arrows are the forces, and the green arrows are the fixtures.

I am running Solidworks with XP x64, but the computations are run on a server on my network. Moving to x64 will make a big difference.

Quote:

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Originally Posted by na94

Also, what environment are you running in? I am trying to do some external CFD in 3D with WinXP x32, however, I receive errors about not having enough continuous free memory, so I can only solve a 2D domain. I will be upgrading to windows 7 x64 tonight in order to take advantage of my processors and additional memory. Any advice on this front?

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What 3-D CFD application do you plan to use with Windows 7x64? Thanks.

Rick

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Originally Posted by Rick Ross

What 3-D CFD application do you plan to use with Windows 7x64? Thanks.

Rick

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SolidWorks Flow Simulation.

Ah, I notice the forces now. Explains the stresses =P

I'm assuming the roll-hoop is a multi-part surface?

The hoop itself is not, running from the floor, through the bend and back down to the floor. I specifically designed it to be one piece.

Quote:

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Originally Posted by na94

SolidWorks Flow Simulation.

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SolidWorks Flow Simulation is not capable of useful formula car aerodynamics, for several reasons: (1) it doesn't handle viscous effects or real boundary layers; (2) the brick meshes aren't accurate enough at any reasonable mesh size, nor is the mesh control fine enough to produce small elements where you need them and larger elements where appropriate; (3) it can't run the 10M to 25M element meshes you need to accurately analyze a half model of a simple formula car.

There are some other minor issues. I wouldn't waste your time, you'll just get bogus results, models that never converge, and system crashes.

Also, unless you're very experienced at CFD on formula or sports racing cars, you're unlikely to model the problem correctly. There are lots of little techniques and tricks of the trade that it takes years to learn. I have a PhD in mechanical engineering, a strong academic background in fluid dynamics, and a fair bit of practical aerodynamics experience, and I wouldn't attempt CFD on a formula car myself.

I would try to find someone who is a CFD expert, preferably with some experience with automotive CFD, and who has access to proper CFD software and convince them to do your aero design.

On the main roll hoop, if I'm seeing it correctly, you aren't in compliance with the GCR. There is a minimum width of the legs where they attach to the floor.

Nathan

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Originally Posted by nulrich

I would try to find someone who is a CFD expert, preferably with some experience with automotive CFD, and who has access to proper CFD software and convince them to do your aero design.

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I am a current member of the Team for Advanced Flow Simulation and Modeling at Rice University (http://www.tafsm.org/). Finding an CFD expert should not be an issue.

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Originally Posted by nulrich

On the main roll hoop, if I'm seeing it correctly, you aren't in compliance with the GCR. There is a minimum width of the legs where they attach to the floor.

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Quote:

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Originally Posted by 2009 SCCA GCR 9.4.5.E.5

One (1) continuous length of tubing shall be used for the main hoop member with smooth continuous bends and no evidence of crimping or wall failure. The radius of bends in the roll cage hoop (measured at centerline of tubing) shall not be less than three (3) times the diameter of the tubing. Whenever possible, the roll cage hoop should start from the floor of the car, and, in the case of tube frame construction, be attached to the chassis tubes by means of gussets or sheet metal webs with support tubes beneath the joints to distribute the loads. It is recommended that gussets be used.

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I assume this his what you are referring to. IIRC, I based the radius of my bends off of this.
R=3*1.375" = 4.125" I'll check my model when I get back to it on Sunday.

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Originally Posted by DMac

I am a current member of the Team for Advanced Flow Simulation and Modeling at Rice University (http://www.tafsm.org/). Finding an CFD expert should not be an issue.

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I apologize, I misread the previous posts and thought you were using SolidWorks Flow Simulation, but it was "na94."

CFD expertise is helpful, but direct experience with formula cars is necessary as well...or at least access to someone who has that experience. Very different from road cars or aircraft.

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I assume this his what you are referring to. IIRC, I based the radius of my bends off of this.
R=3*1.375" = 4.125" I'll check my model when I get back to it on Sunday.

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Nope, I was referring to part of 9.4.5.A: "...On Formula cars and single seat Sports Racers the vertical members of the main hoop shall not be less than fifteen (15) inches apart (inside dimension) at their attachment to the chassis."

Nathan

Quote:

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Originally Posted by nulrich

I apologize, I misread the previous posts and thought you were using SolidWorks Flow Simulation, but it was "na94."

CFD expertise is helpful, but direct experience with formula cars is necessary as well...or at least access to someone who has that experience. Very different from road cars or aircraft.

Nope, I was referring to part of 9.4.5.A: "...On Formula cars and single seat Sports Racers the vertical members of the main hoop shall not be less than fifteen (15) inches apart (inside dimension) at their attachment to the chassis."

Nathan

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Accepted. I will be using Fluent for my CFD analysis.

I see what you are referring to. I think that I will decrease the angle of the hoop from 180 degrees to a smaller angle that meet this requirement. Nothing a few geometric calculations can't solve.

:thumbsup:I just want to say thanks to everybody for the constructive feedback on my design.:thumbsup:

Quote:

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Originally Posted by DMac

I assume this his what you are referring to. IIRC, I based the radius of my bends off of this.
R=3*1.375" = 4.125" I'll check my model when I get back to it on Sunday.

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Also notice 2009 GCR 9.4.5.A

"....On Formula cars and single seat Sports Racers the
vertical members of the main hoop shall not be less than fifteen (15)
inches apart (inside dimension) at their attachment to the chassis...."

Also don't forget this when getting the 15" of separation.

"Main hoop: 4 bends max., totaling 180º ± 10º"

Good to know, I wasn't expecting a lot from something that could run on mydesktop :p

My interests are purely educational, although I'll see if I can locate a copy of Fluent somewhere for fun.

Quote:

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Originally Posted by nulrich

SolidWorks Flow Simulation is not capable of useful formula car aerodynamics, for several reasons: (1) it doesn't handle viscous effects or real boundary layers; (2) the brick meshes aren't accurate enough at any reasonable mesh size, nor is the mesh control fine enough to produce small elements where you need them and larger elements where appropriate; (3) it can't run the 10M to 25M element meshes you need to accurately analyze a half model of a simple formula car.

There are some other minor issues. I wouldn't waste your time, you'll just get bogus results, models that never converge, and system crashes.

Also, unless you're very experienced at CFD on formula or sports racing cars, you're unlikely to model the problem correctly. There are lots of little techniques and tricks of the trade that it takes years to learn. I have a PhD in mechanical engineering, a strong academic background in fluid dynamics, and a fair bit of practical aerodynamics experience, and I wouldn't attempt CFD on a formula car myself.

I would try to find someone who is a CFD expert, preferably with some experience with automotive CFD, and who has access to proper CFD software and convince them to do your aero design.

On the main roll hoop, if I'm seeing it correctly, you aren't in compliance with the GCR. There is a minimum width of the legs where they attach to the floor.

Nathan

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I keep remember things. GCR requires bracing forward from the main hoop.

Thanks for remembering. It's easier than digging through the GCR myself. ;)

Quote:

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Originally Posted by na94

Good to know, I wasn't expecting a lot from something that could run on mydesktop :p

My interests are purely educational, although I'll see if I can locate a copy of Fluent somewhere for fun.

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"OpenFOAM" is a public domain CFD application, but I think that it may require a Linux/Unix platform.

GCR also states if you go over the 180 deg bend you must use the next higher tubing classification. ( but you can exceed 180 )

Quote:

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Originally Posted by Rick Ross

"OpenFOAM" is a public domain CFD application, but I think that it may require a Linux/Unix platform.

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I have played around with OpenFOAM, and it does a lot more than CFD, however Flow is a far sight easier to use.

I would suggest that anyone designing a race car would have the appropriate rulebook(s) in one hand and a creative tool (mouse, pencil, ?) in the other.

That's probably considered "old school" though. :)

Just a coupe quick suggestions:

1) Finite element analysis can be tricky. Without a good amount of experience and understanding of the underlying theory, it is easy to get a incorrect results. One big pitfall of the analysis is that even though the results are incorrect, you will still get a fancy looking colorful picture to incorrectly base design decisions on... In the case of your chassis analysis, your model is over-constrained. By using fixed constraints throughout the model you are adding artificial stiffness to the chassis. It is especially visible in the second picture. If you were to cut off the chassis behind the front suspension points and re-run the analysis, you would get the exact same result.

2) Chassis design should be secondary to nearly every other system. The chassis is simply there to connect the dots. By starting with the suspension design, aero, and packaging, you will be able to connect the dots and hold everything together in its "optimum" place in space. Starting the car design with the chassis and adapting everything to fit inside it isn't ideal.

Keep us updated on the progress. Good luck, and have fun!

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Originally Posted by Billy Wight

The chassis is simply there to connect the dots.

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I had not thought about the design like this. I just had an "eureka" moment. Can't wait to build all of the "dots" first.

I have reconsidered my design process. I am starting from square one more or less. Tonight, I laid out a "jig" to design my car on. Its dimensions are based on the min and max dimensions in the 2010 GCR. It represents the maximum width, maximum overhangs, and minimum wheelbase. In the picture, the tires are constrained against the outside of the plate. Their position will change accordingly as my suspension design progresses.

The wheels that I am using for the model (so far) are 13 inch BBS. The front tires are modeled after Hoosier 43289 slicks, and the rear tires after Hoosier 43293 slicks.

Quote:

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Originally Posted by problemchild

I would suggest that anyone designing a race car would have the appropriate rulebook(s) in one hand and a creative tool (mouse, pencil, ?) in the other.

That's probably considered "old school" though. :)

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The new GCR is open on the computer whenever I am in SolidWorks.

Why minimum wheel base?

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Originally Posted by S Lathrop

Why minimum wheel base?

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That distance is just a placeholder for now. I needed a distance to separate the axle centerlines, and I have not decided on an actual wheelbase.

This afternoon, I was quite productive. I designed and modeled some motor mounts for the GSX-R1000 and the spindle for the center-lock rims. I began designing the upright.

If you get to design the upright from the ground up, do a radial mount caliper. Radial mount should be better all the way around.

Wilwood has some cheap 4 piston calipers that are ok.

PFC has a new set of radial mount calipers that are very, very nice. They are expensive though.

Quote:

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Originally Posted by Wren

If you get to design the upright from the ground up, do a radial mount caliper. Radial mount should be better all the way around.

Wilwood has some cheap 4 piston calipers that are ok.

PFC has a new set of radial mount calipers that are very, very nice. They are expensive though.

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How is the radial mount an improvement over standard post mount or floating mount calipers? I tried to find a coherent answer through Google, but I did not have any success.

Anybody? :confused:

Plans for this afternoon are working more on the upright and the rear hub. Next part will be suspension.

Mountings can influence caliper strenght and torque loadings during brake application.

I see. A normal post mounted brake is mounted in single-shear usually.

Look at the geometry of the force developed at the brake pads and the mounting of the caliper.

Radial mount calipers allow the upright to be 'wider' at the mounts, as well as allows the mounts to be closer to the rotor centerline.

I am using a Wilwood Powerlite 4 piston for the rear brakes on my F600. It is a nice light weight radial mount. From what I understand some DSR's use them also.

Quote:

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Originally Posted by DMac

This afternoon, I was quite productive. I designed and modeled some motor mounts for the GSX-R1000 and the spindle for the center-lock rims. I began designing the upright.

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DMac,

Like the chassis, the upright is just a fancy bracket that connects the dots. I suggest designing the suspension kinematics first, that will determine where your outboard pickup points as well as your brake packaging, then design the upright around that. And as others have said, radial calipers are the way to go.

I have worked out some of the geometry on the front suspension. For now, rod ends are just floating inside the wheel, waiting to be connected by the upright. I am designing around an unequal length, non-parallel a-arm setup. I am going to add in some anti-dive to keep the front wing from dragging under braking. Currently, the a-arms are parallel and in a position that gives zero camber and castor. The next step is positioning the a-arms to give the proper amounts of camber, castor, and anti-dive.

Front track: 1600mm 63in
Rear track: 1550mm 61in
Wheelbase: 2590mm 102in
Wheelbase/F Track: 1.619
Millimeter values are exact

With your listed track values, it looks like you are planning to run 8" front rims, bringing the max width to the max allowed 72" width of the car. Don't forget that the tires stick out a bit past the edge of the rims.

Quote:

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Originally Posted by RobLav

With your listed track values, it looks like you are planning to run 8" front rims, bringing the max width to the max allowed 72" width of the car. Don't forget that the tires stick out a bit past the edge of the rims.

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My maths are a bit off tonight, but in the model, the outside of the section width on each tire is constrained to a 70" distance. The final track number will come from there.

Don't worry, I have not forgot about my current FB endeavors. Assorted tin-top projects have kept me away (wing design and motor rebuild for the Bimmer).

Last weekend, I worked tech at the Queen of Hearts Double National at MSR Houston. During post-race impound both days, I was able look over the RFR F1000 quite closely and pick the brains of David Burkett's crew. Thanks to Scott Hanba from TMG for answering all of my questions! :beer: Too bad assorted gearbox gremlins kept them from working on dialing-in the car (and running full races).

My impressions of the RFR-009:
-Astoundingly low to the ground (it was the only car that had clearance issues on the impound scales)
-Quality fit and finish :thumbsup:
-Strange body panel breaks
-Not using Dzus fasteners on the panels would make removal difficult
-Front wing upper elements looked weak (could see fibers on one already)
-Rear Sway Bar adjuster cable obscures part of the rain light
-(Per Scott) Very thin body panels (thinner than the Stohr)
-Chunky muffler hanging out
-The Dzus fasteners on the helmet surround are a royal pain to get off (took the surround off for Burkett in impound) (see photo) :thumbsdown:

Overall, I thought that the car looked great, and I can't wait to take them on next season. Much has to happen between now and then! :ha:

I am getting back to the computer tomorrow full of inspiration. Hope y'all enjoy the photos.

Looks like they were not running the chimneys - comments? Thanks, Clark

add additional cooling via improved extraction, but only needed for hot weather running.

GC

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Originally Posted by glenn cooper

add additional cooling via improved extraction, but only needed for hot weather running.

GC

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It was cold and damp Saturday morning, while Sunday was cool and clear. Just wait for those Texas summers!

Over the last few months, I have had to shelve my FB project for plenty of reasons. Keeping an Alfa Romeo running and fixing an M3 for One Lap of America (coming out of 9 at Hallett)...overcoming a hand injury and round two of swine flu...last but not least, moving to Atlanta for the summer to work. I have access to SolidWorks at work and will work on the car in spare moments with the goal of having the design done by August.

I realized that I jumped into this project months ago without taking a moment to define what I am aiming for in this design.

Problem Statement: Design and construct a competitive (maybe not initially ;) ) F1000 car in compliance with the 2010 SCCA GCR.

Criteria for Design:
Weight: less than 775lbs
Dimensions from GCR requirements (WB = 1.618*W)
Standard motor mount points with adaptors for various engines (GSXR first)
Radial-mount calipers
Center-lock rims
Provisions for open or LSD
Fit all driver sizes <6'6" <275# with proper angle for HANS device

Work was light today, so I was able work on the suspension design with a simple upright. Based on rough calculations, each arm should be around 20-21" in length. The design uses 1"x.120"wall tube and 1/2" rod ends sleeved down to 3/8". Right now, the assembly is too constrained to test the motion. I am going to go through and remove all of the unnecessary ones and test the motion of the assembly.

I know this iteration may just be an exercise to hone your modeling skills but may I offer some critique.

1) DO NOT use rodends for the UPPER OUTBOARD Joint. You'll want to fashion a way to use a mounting block with SHIMS and use a spherical bearing. If you use a rodend like this you won't be able to make camber changes without changing toe.

2) Lower ball joint...make sure bolt is in DBL SHEAR and use as large a spherical bearing as possible.

I have other suggestions but I don't want to fill up this page.

Regards
Gary Hickman
Edge FB #76

Quote:

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Originally Posted by ghickman

I know this iteration may just be an exercise to hone your modeling skills but may I offer some critique.

1) DO NOT use rodends for the UPPER OUTBOARD Joint. You'll want to fashion a way to use a mounting block with SHIMS and use a spherical bearing. If you use a rodend like this you won't be able to make camber changes without changing toe.

2) Lower ball joint...make sure bolt is in DBL SHEAR and use as large a spherical bearing as possible.

I have other suggestions but I don't want to fill up this page.

Regards
Gary Hickman
Edge FB #76

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PM sent. Thanks for the help!