"active" Rear Spoilers

[oj 89]

As part of the college course I'm currently enrolled on, I 'have to' build a project, and perform all the associated stuff to go with it; including presentations, a logbook, market research, and (hopefully) building my designs.

It is the market research I'm dealing with here. As a car forum, I felt it best to come to you first, as you're most likely to understand my aims with this project.

My idea(s) are as follows:

(1) A hydraulic-actuated air dam kit (think Bugatti Veyron/ Mclaren MP4-12C), supplying all the mechanical and electronic devices, including a pre-programmed PIC-logic arrangement, that you would need to retrofit your very own lifting rear spoiler. Admittedly, the advantages of this kit would generally only be seen on speeds in excess of the national speed limit, but having the option to install it on your 1.0 Arosa is my aim, not getting into a discussion over the 'usefulness' of such a kit.

(2) Maybe the more popular kit option would be a 'TT-esque' extending spoiler kit. This kit would include, again, all the logic and mechanical devices to be fitted into the customer's either stock, or custom spoiler.

The two kits would be supplied as an addition to whatever spoiler you as the customer wish to have, meaning that the customer could 'dissect' their stock spoiler/wing arrangement and retrofit either kit inside it, or, if they have an aftermarket solution, it could be attached to this also.

The only real problem I'm running into (other than hydraulic drive for the air dam. Any suggestions welcome!) is the risk of supplying an 'unfinished' kit to the public, who may have in mind that they are buying a complete spoiler, when in fact, they are only buying the drive for their existing setup.

Thank you for reading anyway, the form is here for completion.

No personal details will be taken, and all information will be treated with the strictest confidentiality, only being released as part of the research for my project, and that will only be seen by the relevant education authorities.

Thank you for your time.

[davey l wrx]

A small electrically driven hydraulic pump would supply what you need, constant speed, constant output. Basically what was fitted in the back of a Hercules transport plane to power ther ramp and door and the brakes when it was on the ground. If needed there was a lever so it could power all the flying controls, it was that powerful. If my memory is correct it was rated at about 3000psi.

Can't think of what else might be needed but i'm sure the Veyron has a radiator for the hydraulic fluid. That could be a limiting factor if it was a retrofit kit!

[lewisscoob]

Have you thought of one like the front of the fezzer 458? It's changes in angle with speed due to its physical properties.

Then there's no need to worry about hydraulics and any assciated problems.

[oj 89]

Cheers for the input guys. I've actually got a bit further along. I'm in contact with a company about electronic-hydraulic conversion, and atm am just struggling with the forces involved. At best guess so far, the force on the rear wing is likely to be around 90lb/ft at 70. So its not going to change the world. The main reason i posted it was mainly for the market research side of it. I need to make it a worthwhile project apparently, and while i do have quite a bit of positive input, more the merrier and all that

Lewis, thanks for the suggestion, but 1. Fezza's got a wind tunnel for escapades such as that, whereas i havent, and 2. Its an electronics project. While moving bits with the wind to make downforce would be cool, it wouldnt suit the profile for the project. Still! I'll bear it in mind if ever i'm bored with the scoob besides, the problems and headaches are part of the fun!

Davey, as dar as the radiator was concerned, the reason the veyron has it is because the hydraulic drive constantly runs off the engine (but i suppose with 1000hp, it it has plenty to spare!). Part of the project is that it cannot run off the engine power (for obvious reasons). It would make its being an 'enthusiast-fitted' kit impossible to produce. Therefore, an EHA (electro-hydraulic actuator) is spot on for the task. Only active when told to be, minimal fluid required, minimal space required! (The one i am interested in is 15cm long!) And the way i am designing the kit, the eha can basically be put anywhere in the car, and just a simple tube needs to go to the slave cylinders.

Again, thanks for taking the time to reply.

[davey l wrx]

Will there be a need for an accumulator or damper in the system!

Usually when the hydraulic circuit is 'idling' it's just a neutral flow of fluid round the circuit. In your system as the brakes are applied and the rear wing becomes a brake that could be a sudden big load on the system, the accumulator would smooth out any shock effect and maintain the correct hydraulic pressure!

I also assume you would need some sort of hydraulic resevoir and would the system be self bleeding? The easier it is for the avarage punter the better

Edited February 20, 2013 by davey l wrx

[oj 89]

Will there be a need for an accumulator or damper in the system!

Usually when the hydraulic circuit is 'idling' it's just a neutral flow of fluid round the circuit. In your system as the brakes are applied and the rear wing becomes a brake that could be a sudden big load on the system, the accumulator would smooth out any shock effect and maintain the correct hydraulic pressure!

I also assume you would need some sort of hydraulic resevoir and would the system be self bleeding? The easier it is for the avarage punter the better

Funnily enough, thats why I'm trying to build a stand-alone system. If I try to use anything on the existing car, it complicates matters beyond measure. My actual plan involves a closed loop, where the EHA pushes the slave cylinders "up" and when the actuator retracts, the resulting vacuum pulls and holds the rear wing down. Its relying on a sound system, but the amount that people would be looking to pay (I've got some people from my questionnaire that are willing to pay £200+!) I'd expect them to either know how to properly seal the system, or get someone who knew how to do so to fit the kit for them. I think I'm using a small reservoir. I don't have the designs on me atm, but in a sealed system, bleeding once, and that should be it, without leaks, of course, shouldn't it?

[davey l wrx]

I was one of the ones who filled the questionaire in and i did tick the 200+ box because i didn't think it could really be done for less!

If you include the pump, wiring to run it, actuators, fluid, hyd-resevoire, etc the cost will soon build.

What fluid would you use.... brake fluid would work but if you had a leak somewhere the last thing you need is brake fluid squirting round the car at high pressure sripping all the paint in the boot as it goes. Aircraft grade fluid would work, but it's expensive and hard to get hold of for joe public though it doesn't strip paint like brake fluid does.

Then there's the how do you fit the kit, seal everything up so there's not water pishing into the boot all the time so some seals would be needed. Fitting instructions, cutting/drilling guides, i really didn't think it could cost less than £200 and be reliable.

Also how will it be triggered to work like the veyrons air brake?

Will it be wired into the brake lights?

Will it be connected to the pedal?

will it connected to the slave/master cylinder?

As you wouldn't want the the thing going to full deployment if your sat in traffic and tap the brake pedal.... Would it somehow be graduted in it's operation so at slow speeds it wasn't fully used but if you were on say a track day, hoofing it down a straight to the hairpin bend you'd want it's full effect.

Edited February 20, 2013 by davey l wrx

[oj 89]

I was one of the ones who filled the questionaire in and i did tick the 200+ box because i didn't think it could really be done for less!

If you include the pump, wiring to run it, actuators, fluid, hyd-resevoire, etc the cost will soon build.

What fluid would you use.... brake fluid would work but if you had a leak somewhere the last thing you need is brake fluid squirting round the car at high pressure sripping all the paint in the boot as it goes. Aircraft grade fluid would work, but it's expensive and hard to get hold of for joe public though it doesn't strip paint like brake fluid does.

Then there's the how do you fit the kit, seal everything up so there's not water pishing into the boot all the time so some seals would be needed. Fitting instructions, cutting/drilling guides, i really didn't think it could cost less than £200 and be reliable.

Also how will it be triggered to work like the veyrons air brake?

Will it be wired into the brake lights?

Will it be connected to the pedal?

will it connected to the slave/master cylinder?

As you wouldn't want the the thing going to full deployment if your sat in traffic and tap the brake pedal.... Would it somehow be graduted in it's operation so at slow speeds it wasn't fully used but if you were on say a track day, hoofing it down a straight to the hairpin bend you'd want it's full effect.

Brake fluid was what I was thinking tbh. And while I agree, you'd not want the job to be done half-cocked using it, There's no reason why you can't put a massive warning on the box/tubing/somewhere in the kit saying 'make sure you do this right, else you're going to strip the paint off your car.'

At the moment, I'm working on 2 variables, the speedometer, and the brake light switch. In the control box, I'll have a potentiometer to adjust "minimum speed deployment." So if you want it to pop up every time you touch the brake, like on a racetrack, then you can, and if you want to then adjust it so it will only lift at, say 50mph+ on the road, you can. I was considering putting in another input that monitors the braking input, and if that goes above a certain level, it deploys regardless of the speed. As a kind of safety feature. But that would be an "If people wanted it" kind of thing.

As you rightly say, the price would hinge around the expense of the EHA. If the company I'm in contact with only wants £50 or so for the actuator, per unit, £100-150 would easily cover the rest of the equipment. If they wanted £150+, however, it will always be a struggle to keep it at a 'reasonable' price for the kind of people I want it to be sellable to.

[davey l wrx]

Are you expecting it to work off one actuator.

All the ones i've seen on prodution cars have 2.

[oj 89]

Are you expecting it to work off one actuator.

All the ones i've seen on prodution cars have 2.

The capabilities of the actuator I'm looking at will be able to deal with 2 slave cylinders with ease. To explain, the EHA will be situated inside the car somewhere, with a pipe leading to 2 slave cylinders mounted on/in/around the rear spoiler. Its more speed that is required more than actual capability pressure-wise.

[spect]

Have you considered a pure electronic/electrical solution? If you are using logic circuits you may be able to piggy back off the canbus directly in the boot and use servomotors to provide the drive - no nasty fluids and probable weight saving. Cost may be less too.

[oj 89]

Have you considered a pure electronic/electrical solution? If you are using logic circuits you may be able to piggy back off the canbus directly in the boot and use servomotors to provide the drive - no nasty fluids and probable weight saving. Cost may be less too.

I had thought about it; in fact, I had designed the logic control system so that if one desired, you could have an electronically actuated spoiler, like you see on the Audi TT's and 'high end' sports cars now, which pops up to a specified 'mark' above the desired speed. But the idea isn't just for canbus based cars, or even ECU'd cars. Its supposed to be universal, to jump in any car, with a spoiler, or one fitted aftermarket-like, and bolt the kit on, job done. Hence the simplicity (and to an extent the risk of expense) of the design. The less components, the less likely something will go wrong, being my thinking. Thanks for the suggestion though

[spect]

It would not need canbus though as I was just trying to suggest electrical motor rather than hydraulic. It could be simple switch on/off, speed sensitive or even variable by speed. Anyway, go for it

[davey l wrx]

For a car electrial would be easier to install and set up.... but. Hydraulics can react quicker and there wouldn't be the issue of mechanical linkages wearing out on the electric system.

[monsterenergy]

Could ye nae use a similar idea to an F1 pump used for gear changes on a Ferrari/Maserati gearbox.

Like for like F1 pumps for Alfa Romeo's can be picked up cheap and they pump transmission fluid.

The reaction time for this must be pretty quick.

Maybe a crap idea but just thought I'd throw in my tuppence worth.

Alfa Selespeed Pump

Edited February 23, 2013 by monsterenergy

[davey l wrx]

Could ye nae use a similar idea to an F1 pump used for gear changes on a Ferrari/Maserati gearbox.

Like for like F1 pumps for Alfa Romeo's can be picked up cheap and they pump transmission fluid.

The reaction time for this must be pretty quick.

Maybe a crap idea but just thought I'd throw in my tuppence worth.

Alfa Selespeed Pump

I think he's trying to keep costs for the kit below £200.

That pump alone is on offer for £253 at about half price......

I did have another thought on this today and was wondering about the kit, would all the parts used would have to be approved for use in/on a car like TUV tests. A ssurely they would have to be declared safe if there was an accident so they wouldn't leak, cause a fire, etc!

I may be worng but there is something in the back of my head saying that anything fitted needs to be approved by some official body!

Edited February 23, 2013 by davey l wrx

[oj 89]

I did have another thought on this today and was wondering about the kit, would all the parts used would have to be approved for use in/on a car like TUV tests. A ssurely they would have to be declared safe if there was an accident so they wouldn't leak, cause a fire, etc!

I may be worng but there is something in the back of my head saying that anything fitted needs to be approved by some official body!

Thats a very good point I hadn't thought of! Perhaps something for if it goes into production. The way the projects looking, the meat of the plan will be carried on outside college. I'll note it down for things to look at though