my TIGRA AERO PROJECT

[fabrio.]

Hello boys.
After more two years I write new message for desrcribe to you what I am building.

If you remember, I want to cover the rear trunk of my car for to create a boat tail, but at high speed this boat tail create more lift that is dangereus at hi speed cornering.
I thought that an active spoiler is the best solution for the safety and the preservation of good aerodynamic.
So, I have installed a wiper motor to be linked to the spoiler.
This motor is drived by three relays for activation and reverse turn.
An simply circuit contain a potenziometer to be connected to the spoiler or at the motor for measure the angular inclination.
Two electrics limit are added for limiting spoiler range.
So, I bought an android device and an IOIO board ( see: https://www.sparkfun.com/products/10748) that provide 48 pin for digital I/O, analog input (AD converter), PWM, SPI and I2C interfaces and USB plug or bluetooth stick for android connection.
I wrote big part of necessary software (app android) that control the spoiler in manual or automatic mode.
Now I can control the motor in manual mode through two button up and down direction.
For automatic mode, I use 3 axis accelerometer android embedded for understand the forces that affect the car during driving, I want add others two signal for an best management: brake signal and vehicle speed, but I need to add an frequency/voltave converter for connection at the IOIO.
Considerable time is required for to complete this work, the difficulty comes from the algorithm to the engine control strategy.
What do you think?



video

motor controlled by android with accelerometer

http://www.youtube.com/watch?v=50Uwa...pmJGHPUZQIkoHg

[kach22i]

Great project, I had not seen this one before.

[Cd]

That is impressive !

[Piwoslaw]

Fabrio, are the wheel spats and undertray still installed? Did they get any damage over the last years?
And do you have to remove all of your mods before the annual technical exam?

[fabrio.]

Originally Posted by Piwoslaw

Fabrio, are the wheel spats and undertray still installed? Did they get any damage over the last years?
And do you have to remove all of your mods before the annual technical exam?

I don know in Polland but in Italy we can't use wheel well covers because forbidden, but soilers, sideskirts are permitted.
Undercover is not visible and I don't removed it as front and rear spats if small.
My diffuser is broken one year ago and I have not replaced.
I have in plan to remake the diffuser and add a complete undercover, but at this moment I want to finish the rear active spoiler: it is the first thing on my mind.
Now I am studing vehicle dynamics and wing aerodynamic: I need to understand how I can to realize the algoritm for managing the spoiler movement.

[fabrio.]

this picture about the actuator of spoiler



and a partial view of reardec cover

[AndrzejM]

Fabrio, I don't know if accelometer is a best solution to control spoiler, you should combine that with some kind of speed signal - GPS or VSS.

As I understand you want to build something similar to Pagani Huarya's aero stability system. Good luck, I'll keep my fingers crossed.

[fabrio.]

this is scheme cardroid



MDU: motor drive unit
FVC: frequency to voltage converter ( to connect to vehicle speed sensor)
Cardroid uses not only 3 axis accelerometer but also signall throttle and signal brake.

[AndrzejM]

That's nice! So now you just have to program the spoiler angle vs speed and 3D accelometer signal.
You can use that as a aero brake, stability control when cornering and improving aero when going straight... That's a cool project. Can't wait to see the results.

[fabrio.]

somes pictures of cardroid application:



start the application: it shows the cardroid logo, its calibration state, IOIO connection state, and GPS state (gps is used for calibration vehicle speed sensor)



User menu: manual and automatic spoiler management, setup ecc..



in manual mode



page setup: calibration 3 axis accelerometer with car on horizzontal position, and settig handling request (normal, sport and race) with different automatic spoiler management.



further development: to add choice road surface (dry, wet, ecc) obvious english language.