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Old 07-14-2014, 09:26 PM   #141
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It might be worth having a light that turns on when it returns to the down force position. Just in case something binds, or a wire gets disconnected while it's in the low drag position. The inverse would work as well, light is on whenever it's not fully in the down force position. The failure mode of 'light is burnt out' is a little bit better in the former though.
Prefer warning light only when error condition is detected. It could even output to a race dash. Simple to incorporate.
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Old 07-14-2014, 09:30 PM   #142
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Don't forget the motors have an indicator light for when they're in motion. That would be easy to incorporate. I don't know what happens if they get stopped partway, though.
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Old 07-14-2014, 10:25 PM   #143
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Don't forget the motors have an indicator light for when they're in motion. That would be easy to incorporate. I don't know what happens if they get stopped partway, though.
If the motors get stopped partway, the light remains on

The light turns on whenever those motors are not in the fully up or fully down position...so if it got stuck, that light would remain on.
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Old 07-16-2014, 12:46 AM   #144
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What about a momentary switch on the firewall under the throttle pedal?

Would only go in to low drag at full throttle....no hand off wheel to press button (during gear changes???) etc....
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Old 07-16-2014, 01:10 AM   #145
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What about a momentary switch on the firewall under the throttle pedal?

Would only go in to low drag at full throttle....no hand off wheel to press button (during gear changes???) etc....
Max drag/Downforce during gear changes. Unless flatshifting or momentary delay when the switch is released.
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Old 07-16-2014, 02:05 AM   #146
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Quote:
Originally Posted by FatKao View Post
It might be worth having a light that turns on when it returns to the down force position. Just in case something binds, or a wire gets disconnected while it's in the low drag position. The inverse would work as well, light is on whenever it's not fully in the down force position. The failure mode of 'light is burnt out' is a little bit better in the former though.
Quote:
Originally Posted by Ben View Post
Prefer warning light only when error condition is detected. It could even output to a race dash. Simple to incorporate.
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Originally Posted by [email protected] View Post
Don't forget the motors have an indicator light for when they're in motion. That would be easy to incorporate. I don't know what happens if they get stopped partway, though.
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Originally Posted by fooger03 View Post
If the motors get stopped partway, the light remains on

The light turns on whenever those motors are not in the fully up or fully down position...so if it got stuck, that light would remain on.
Exactly. The light goes on to tell you the wing is changing position. And if it gets stuck, the light stays on -- which is a pretty good system.

Aside from that, I've put a big red decal on the underside of the wing. It's only visible when the wing is in the low-drag position. So if I suspect there's a problem, I can see it confirmed in the rear view mirror.

Quote:
Originally Posted by mx5-kiwi View Post
What about a momentary switch on the firewall under the throttle pedal?

Would only go in to low drag at full throttle....no hand off wheel to press button (during gear changes???) etc....
Quote:
Originally Posted by M.Adamovits View Post
Max drag/Downforce during gear changes. Unless flatshifting or momentary delay when the switch is released.
It's tricky. At the track I'm setting this up for, there are some full-throttle moments where I need no downforce, and other full-throttle moments where I need all I can get. The same goes for a speed sensor. There's a 130-mph kink where I'd like to have the downforce, and a 130-mph straight where I don't need it.

So far, the only condition where I can see I wouldn't want the low-drag position at Willow Springs (my home track) is under any braking. So I'm going to add a second relay to return the wing to high-downforce whenever I touch the brakes. But even so, that isn't going to always be the case at all tracks. I'm surprised that Aeromotions has come up with a solution that uses sensors to move the wing. I'd be hard-pressed to come up with a list of conditions and wing positions that would always work.
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Old 07-20-2014, 10:11 AM   #147
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What'd be really cool is using a gps based actuator control that you could load up different wing profiles for different tracks, from 0-100% with a stepper motor. I kinda searched, but didn't find anything relevant - not to say they don't exist.
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Old 07-20-2014, 10:55 AM   #148
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Originally Posted by GeneSplicer View Post
What'd be really cool is using a gps based actuator control that you could load up different wing profiles for different tracks, from 0-100% with a stepper motor. I kinda searched, but didn't find anything relevant - not to say they don't exist.
Starting with something like this
National Control Devices: Android Relay Control with a Bluetooth Interface
"All" you need is an app that can control the relays based on areas/lines on a GPS map.

Or go fully standalone GPS puzzle box | MAKE (totally unknown to me how many on/off locations it can handle).
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Old 07-20-2014, 01:59 PM   #149
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Overly complex, too many possible failures IMO. Not to say GPS-based stuff isn't used in top tier motorsports, but I wouldn't cobble together and rely on a DIY system. Keep It Simple.
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Old 07-20-2014, 10:56 PM   #150
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GPS based would be a possibility to do through Race Capture Pro. If you can write simple Lua scrip, then you can program almost any output based on almost any input. Using active aero based on GPS location would be in that realm. The system is cheap too.

http://www.autosportlabs.com/
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Old 07-25-2014, 01:08 PM   #151
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It's the cycle of life, a competition to come up with the most complex wing possible
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Old 07-28-2014, 06:31 PM   #152
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Well, it took a few iterations before I had the pivot point right and also had enough leverage to move the wing at 130 mph, where it's generating in the neighborhood of 400# of downforce. It now makes a 14 angle change with a steering-wheel mounted button.

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Active rear wing test-mqdefault.jpg  
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Old 07-28-2014, 06:42 PM   #153
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Fantastic, have you noticed any difference in top speed with the wing stalled...?

I've been reading a link from another thread (going to a lotus page) where their data suggests a basic single plane wing had a drag/cost of approx. 6 hp for 700n of downforce and a mutliplane wing with 1200n downforce had a drag/cost of 13 hp (all approx.)

I am wondering if the benefit of gaining back the 6-12 hp is noticeable on track...what would 12hp be in your car....3-4%?
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Old 07-28-2014, 07:51 PM   #154
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In straight-line testing, I didn't notice any difference at all.

I think I might be (optimistically) looking at what amounts to a 4-hp difference at 125-135mph. My car has 272 hp at the crank.
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Old 07-29-2014, 12:47 AM   #155
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If you find there is no appreciable difference will you retain the system?

Was also wondering if you have any pre and post wing install data...lap time improvements etc...not worried about accurate just interested to see what difference the wing made for you.

My "Classic Japanese" class is not really aimed at allowing aero but I sometimes wonder if it isn't worth setting the car up for a "with" aero and a "without" aero...could use it for track days and other more open classes (different race meetings) where the car gets outgunned in the 2.5 to 3.0 litre class it gets "upgraded" to. Not to mention that that class is run in conjunction with open class "sedans"......as part of the over 2.5 litre group and a pretty scary place to be puttering around in
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Old 07-29-2014, 01:30 AM   #156
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If it doesn't make a difference in my lap times, I will dump the 5 additional pounds in a hurry. (I'm sure the pop-up headlamp motors would be useful for some kind of scary Halloweed display here at the house.)

I have a lot of data on my car on this particular track, since I've been going here for 15 years and -- for the past six years or so -- pretty much only drive at this track and with the same car in basically the same configuration. I've been instructing at the track for over a decade, so I think it's safe to say that driver development is not going to increase much in the future. At this point, I can tell you what my lap time will be within a few tenths of a second based only on ambient and track surface temperatures.

And because my car's aero bolts on, I have a fair amount of data of my car both with and without the wing and splitter. It gets me about a second and a half per lap, which is more than aero would get my car at most tracks, but that's because Willow Springs is a very fast track, with turns 1, 2, 6, 8 and 9 (of 9) all being 90-mph or more corners. For the fastest corner on the track (8) the aero hurts me, since I'm flat on the gas and 130-mph through the corner with or without aero. (So it's only adding drag.) But for the other corners, my speed through the corner is helped by the wing and splitter -- in a way where an 80-mph-or-less corner is not going to see nearly as significant an increase, since downforce increases exponentially with speed.

Now, people make something of a mistake when they think that taking the aero off is going to mean higher top speeds in the faster sections of the track. I have less drag without the splitter and wing, but I also can't take the corner before any given straight as fast without the aero, so my initial speed on the straight is lower, which limits my ultimate top speed.

Having variable drag reduction would (should? could?) change that. Theoretically, I should be able to take the corners just as fast, but then be able to drop some of the drag on the subsequent straight.

As I've mentioned before, I'm still not sure the one change in the wing will make a big enough difference to measure on my car. Unlike F1 cars, which have carefully designed aerodynamics over every inch of the chassis, a production car is more like a brick with wheels. Whether this small reduction in overall drag will make an appreciable difference is something I won't know until I can run back-to-back laps both with and without it.

With:



Without:

Attached Thumbnails
Active rear wing test-kx1qt.jpg   Active rear wing test-nov-18-2009-otr1258741041.jpg  
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Old 07-31-2014, 09:26 PM   #157
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Quote:
Originally Posted by GeneSplicer View Post
What'd be really cool is using a gps based actuator control that you could load up different wing profiles for different tracks, from 0-100% with a stepper motor. I kinda searched, but didn't find anything relevant - not to say they don't exist.
I wonder if AIM has some output channels you could tie into the track maps. Pretty cool idea. It would take more than I would be willing/able to do though.
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Old 07-31-2014, 10:29 PM   #158
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Are you active on Pelican and have a 3.6 in that car Jack?
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Old 08-01-2014, 12:56 PM   #159
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A little off topic, but perhaps you could fit one or two to a front splitter and have it drop the front angle down to grab more air and increase drag? Assuming it doesn't contact the tarmac. Could tie it into the same switch if you don't use drag while cornering; I imagine if there's any increase to the front downforce you'd risk oversteer..
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Old 08-01-2014, 06:12 PM   #160
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Are you active on Pelican and have a 3.6 in that car Jack?
That's me.
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