Vehicular Design Idea(serious discussion pls)
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I was thinking yesterday when i went home, about the inherent difficulties of any vehicle when on a circuit, and when cornering. Basically a lap time is largely decided by the cornering speeds as well as the exit speed from a corner onto a long straight. If we could raise the speeds of a vehicle in a corner, we would significantly also increase the exit speed, and thus the speed on the straightway as well.
Now in a corner, a vehicle's grip is very important. Currently grip can be controlled thru aerodynamic means, and also the uh........
mechanical design of the whole chassis and suspension systems as a dynamic whole. we know that in racing and on-road use, many cars are fitted with traction control(TC) to help improve grip in corners by limiting the wheelspin. In some cars, esp the 4WDs, like the EVO and the Skyline GTRs, they have rather sophiscated electronical systems like AYC and ATTESA E-TS.
These systems help to detect which wheels need more grip and such, and distribute torque and power to the respective wheels as needed, or it cuts off the power to a certain wheel to limit wheelspin for maximum traction.
Now there can only be so much that engineers and designers work on the aspect of mechanical grip on a car. I was thinking about it yesterday and i thought about looking at the problem from an aero point of view. I do not know if other car manufacturers and designers have ever thought about this idea for a solution.
Now, if a high tech sports car like the Enzo, Carrera GT, Murcielago or the SLR do not need a physical wing on the car, i guess it means we are technologically advanced now that our car designs can have a lot of minute aero devices on the car. Also as far as i know, the Murcielago, SLR and Carrera GT have some simple form of movable aero devices, which allows a variation of downforce as and when needed.
If a car was designed with movable aero devices at all 4 corners of the car, and a system installed to detect downforce needed and adjust the downforce on each corner of the car, that would certainly make the car much faster. Eg. under accel, a car's weight transfers to the rear, sometimes making for poor traction at the front, or sometimes causing understeer(eg. when accelerating out of a corner). if the system was able to detect the resultant loss of grip of the front wheels, it would then adjust the frontal aero devices to generate more downforce at the front end of the car, thus negating the effects of weight transfer. Another would be during cornering, it detects the need for grip on the inside wheels of the car, and adjusts the aero devices on that side of the car, thus giving the car grip on the inside an outside as well, and maximising the grip limit of all 4 tyres. hence combining the 2 eg, we have a car which virtually would be able to self-correct, generating downforce where its needed, and also to reduce downforce when its not needed, such as while on a long straight. I believe such a car would certainly be very very quick. much quicker than the Enzo, Pagani, Carrera GT or the SLR.
The question is, are our technology there yet? The electronical components and the processing power of the computer unit that would have to be installed. I believe the electronic system governing the aero devices would be quite complex and require a lot of processing power. Are our current computer science there yet? Also such a car would face a lot of wear n tear when driven at high speeds, esp the aero devices, are we able to utilise the current level of technology in the design and physics of materials? How about other factors such as the design of durable movable aero devices and the installation of servo motors to move them? reliabilty?
As such this is a concept car question, we shall ignore price for now. What i want to know is, can it be done? What are the problems which might be faced during the design phase and maybe construction phase? -
any comments and suggestions?
would like to get feedback from anyone who knows about electronics, programming and other aspects of engineering. -
you asked for serious feedback. needs some time ..... be patient. someone will reply, hopefully ..... hehe
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how about u? hahaOriginally posted by eutjin:you asked for serious feedback. needs some time ..... be patient. someone will reply, hopefully ..... hehe
a design team would need a network. u think for design purposes a network with enough processing power can be setup? -
PCs nowadays are powerful enough to handle the design stuff you need. but, it really depends what you require. anyway, the bottom line is that computer hardware nowadays is really affordable.Originally posted by HENG@:how about u? haha
a design team would need a network. u think for design purposes a network with enough processing power can be setup? -
Aircraft have been doing this since fly by wire...
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so is it possible to translate this technology into road cars?
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sure it'd work! the tricky part is where to draw the line between increasing the weight of the car with all the additional hydraulics, sensors and such for it to actually create more good for the downforce and therefore, exit speeds then there would be to cause more wear and tear as well as consequential liability to the other performance aspects of the vehicle.
look at the lambo, the porsche or any other car that has such nifty devices incorporated into their aerodynamics. i'm sure the additional weight gains compared to other vehicles in their league were accounted by these more then their luxury items. -
i can only draw...too bad...i dont know much abt cars and parts and its stuff... i can only draw with my hand. hehe From NAFA so if i cant draw...wat a disgrace...hahah
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Well, if we could so accurately and efficiently control the pitching, rolling and yawing movements of the Boeing 747 with simple (ok, not so simple) aero devices like the flapper, ailerons, stablizer and the rudder, I don't see why we cannot achieved active control of a car in motion.
The current technology in Control Engineering already allow us to perform complicated tasks like traction and yaw control. I believe the engineering aspects of performing the task as mentioned by you (controlling 4 corners of the car) is available but the question is suitability.
If I'm not wrong (I don't know the actual operation of the aero devices of them), the Murcielago, SLR and Carrera GT provides for these minute adjustments by adjusting the pitching movement of the car (equivilent to the stabilizer at the rear of the 747), via, as you mentioned, generating a downward force to minimize 'floating'. It is significantly easier to acomplished as we are only dealing with only a degree of movement (or freedom): the axis inlined with the longitudinal direction of the car. In this aspect, I think the engineers are simplifying the problem by limiting to 2 dimensional analysis of the dynamic forces acting on the car in motion (just the pitching).
Now, is there a need to actively control the car in three directions (yaw, pitch, roll). The typical speed of of a car moving into a corner (say in GT races) is, maybe, say less than 200 km/h. At these speed, the effective design of the aero devices needed to sufficently generate a negative lift to counter the iifting forces induced by centrifugal forces (on the inside of the car nearer to the center of rotation) will be a function of the coefficent of lift (a fix set of values depending on the design of the device and the angle of attack), density of air, the free stream velocity and the chord length. We normally will not be able to change the first three, the only variable is the chord length. But at the speed mentioned, the chord length will have to have a significantly long dimension to generate a negative lift to be of any effect. Thus it may not be practical unless a really effective design could be conjured. Also, the problem of adding lift generating devices is the induced drag involved. It ultimately increased the overall drag of your car. (this come to mind of all the spoiler in the market. Most of them are aesthetically-inclined and the design is so awful that it actually is adding a significantly high amount of drag to your car. Slow down your car and burning more fuel at crusing speed)
Just my 2 cents worth ... hey, those things learnt in U is still not that rusty leh....hehe. -
if i had 2 lambos, i'd rip out the aircon, stero and strip down the interor of one, just to make it hardcore. wahahaOriginally posted by tailslide:sure it'd work! the tricky part is where to draw the line between increasing the weight of the car with all the additional hydraulics, sensors and such for it to actually create more good for the downforce and therefore, exit speeds then there would be to cause more wear and tear as well as consequential liability to the other performance aspects of the vehicle.
look at the lambo, the porsche or any other car that has such nifty devices incorporated into their aerodynamics. i'm sure the additional weight gains compared to other vehicles in their league were accounted by these more then their luxury items. -
for your 2nd last para, i think its not so big a problem since i'd mentioned that on the straights the aero devices can move to a "minimum downforce" setting, or even to almost zero. basically right now the 2 questions raised seem to be weight increase and wear and tear.Originally posted by dok gong:Well, if we could so accurately and efficiently control the pitching, rolling and yawing movements of the Boeing 747 with simple (ok, not so simple) aero devices like the flapper, ailerons, stablizer and the rudder, I don't see why we cannot achieved active control of a car in motion.
The current technology in Control Engineering already allow us to perform complicated tasks like traction and yaw control. I believe the engineering aspects of performing the task as mentioned by you (controlling 4 corners of the car) is available but the question is suitability.
If I'm not wrong (I don't know the actual operation of the aero devices of them), the Murcielago, SLR and Carrera GT provides for these minute adjustments by adjusting the pitching movement of the car (equivilent to the stabilizer at the rear of the 747), via, as you mentioned, generating a downward force to minimize 'floating'. It is significantly easier to acomplished as we are only dealing with only a degree of movement (or freedom): the axis inlined with the longitudinal direction of the car. In this aspect, I think the engineers are simplifying the problem by limiting to 2 dimensional analysis of the dynamic forces acting on the car in motion (just the pitching).
Now, is there a need to actively control the car in three directions (yaw, pitch, roll). The typical speed of of a car moving into a corner (say in GT races) is, maybe, say less than 200 km/h. At these speed, the effective design of the aero devices needed to sufficently generate a negative lift to counter the iifting forces induced by centrifugal forces (on the inside of the car nearer to the center of rotation) will be a function of the coefficent of lift (a fix set of values depending on the design of the device and the angle of attack), density of air, the free stream velocity and the chord length. We normally will not be able to change the first three, the only variable is the chord length. But at the speed mentioned, the chord length will have to have a significantly long dimension to generate a negative lift to be of any effect. Thus it may not be practical unless a really effective design could be conjured. Also, the problem of adding lift generating devices is the induced drag involved. It ultimately increased the overall drag of your car. (this come to mind of all the spoiler in the market. Most of them are aesthetically-inclined and the design is so awful that it actually is adding a significantly high amount of drag to your car. Slow down your car and burning more fuel at crusing speed)
Just my 2 cents worth ... hey, those things learnt in U is still not that rusty leh....hehe.
Weight increase would have to be offset by exotic manufacturing methods and materials, to lighten up other components as much as possible. Also i feel that with the existance of high BHP high torque engines like the one in the Veyron and the TVR Spd 12, the increase in weight can hopefully be offset by the installation of a very high BHP engine? a car which has such superior active aerodynamics should be able to uitilise a high bhp engine far more effectively, for example, the TVR Spd 12 was a mediocre vehicle since it was unable to effectively handle its power. with such advanced active aerodynamics, i think the car would be faster, even over a car which has slightly better power to weight ratio.
As for wear and tear, the same usage of exotic materials and high tech "space-age" construction is what i think should be the way, but im not sure about the actual effectiveness of that. any comments? -
Yes, given the amount of power these engines can generate, the weight increase can almost be neglected. These active controlling devices are added to increase the maneuverability of the car when it is deviating from a straight course. Unless, the speed involve are very high, I feel that passive aero-devices (front and rear spoilers) currently employed are enough to achieve good dynamic stability already.
Rather, designers are looking at improving the strutural aspects of the cars these days as they believe it is in these area that the next break-through in car modelling is achievable. Designers are adding innovative designs to improve the car passive aerodynamics: Wiliams' FW26 for example has a short front nose cone to improve air flow both under and above the car, right to the rear wing area. This design is rare and uncommon in F1 although the physics of such aerodynamic design is well understood and used frequently in the aerospace industry. -
for F1, thats because active aero components are banned.Originally posted by dok gong:Yes, given the amount of power these engines can generate, the weight increase can almost be neglected. These active controlling devices are added to increase the maneuverability of the car when it is deviating from a straight course. Unless, the speed involve are very high, I feel that passive aero-devices (front and rear spoilers) currently employed are enough to achieve good dynamic stability already.
Rather, designers are looking at improving the strutural aspects of the cars these days as they believe it is in these area that the next break-through in car modelling is achievable. Designers are adding innovative designs to improve the car passive aerodynamics: Wiliams' FW26 for example has a short front nose cone to improve air flow both under and above the car, right to the rear wing area. This design is rare and uncommon in F1 although the physics of such aerodynamic design is well understood and used frequently in the aerospace industry. -
agreed man.....Thats wad i told heng on the phone...weight is a prob....and the hydraulics....and u cannot make the car 2 dependent on it...cos if it fails then u're just like a F117A...which cannot fly w/o the fly-by-wire systemOriginally posted by tailslide:sure it'd work! the tricky part is where to draw the line between increasing the weight of the car with all the additional hydraulics, sensors and such for it to actually create more good for the downforce and therefore, exit speeds then there would be to cause more wear and tear as well as consequential liability to the other performance aspects of the vehicle.
look at the lambo, the porsche or any other car that has such nifty devices incorporated into their aerodynamics. i'm sure the additional weight gains compared to other vehicles in their league were accounted by these more then their luxury items. -
i hope that you guys haven't forgotten, using high horsepower to offset an increased mass often results in less desirable by effects. firstly, there has got to be more consideration given for the additional stress undertaken by the drivetrain and the increased complexity of the suspension system to bring about some stability during the cornering scenarios.Originally posted by dok gong:Yes, given the amount of power these engines can generate, the weight increase can almost be neglected. These active controlling devices are added to increase the maneuverability of the car when it is deviating from a straight course. Unless, the speed involve are very high, I feel that passive aero-devices (front and rear spoilers) currently employed are enough to achieve good dynamic stability already.
Rather, designers are looking at improving the strutural aspects of the cars these days as they believe it is in these area that the next break-through in car modelling is achievable. Designers are adding innovative designs to improve the car passive aerodynamics: Wiliams' FW26 for example has a short front nose cone to improve air flow both under and above the car, right to the rear wing area. This design is rare and uncommon in F1 although the physics of such aerodynamic design is well understood and used frequently in the aerospace industry.
secondly, there has got to be more leeway given for the braking components which will inevitably suffer greater punishments in achieving an acceptable level of braking for a larger moving mass. remember newton's law of motion? or how the skyline eventually lost to the AE86 in Initial D? (ok bad eg coz its manga)
i think the key to the solution is still to keep the idea simple, with minimal mechanics to achieve maximum effects using sturdy, lightweight materials like kevlar and carbon fibre.
just another tot. aeroplanes use reverse thrust mechanisms during landings to help diffuse the planes' forward momentum during landing. perhaps it would be feasible to incorporate some fuzzy logic, motion sensing thrusters at each wheel running on fuel from the gas tank? lets say u wanna brake, the 4 thrusters fire in reverse, counteracting the forward momentum and shortens the braking distance. during a corner, the sensors detects which wheel is losing grip and the correlatory thruster fires upwards, generating additional downforce on that portion of the vehicle thereby improving overall grip. the car's external would have to undergo major works to accomodate the multi directional firing of the thrusters, but the overall savings in weight could be significant as compared to using all those hydraulics and stuff! so, waddaya think ppl?
(i'm talking cock again ) -
jet thrusters?Originally posted by tailslide:i hope that you guys haven't forgotten, using high horsepower to offset an increased mass often results in less desirable by effects. firstly, there has got to be more consideration given for the additional stress undertaken by the drivetrain and the increased complexity of the suspension system to bring about some stability during the cornering scenarios.
secondly, there has got to be more leeway given for the braking components which will inevitably suffer greater punishments in achieving an acceptable level of braking for a larger moving mass. remember newton's law of motion? or how the skyline eventually lost to the AE86 in Initial D? (ok bad eg coz its manga)
i think the key to the solution is still to keep the idea simple, with minimal mechanics to achieve maximum effects using sturdy, lightweight materials like kevlar and carbon fibre.
just another tot. aeroplanes use reverse thrust mechanisms during landings to help diffuse the planes' forward momentum during landing. perhaps it would be feasible to incorporate some fuzzy logic, motion sensing thrusters at each wheel running on fuel from the gas tank? lets say u wanna brake, the 4 thrusters fire in reverse, counteracting the forward momentum and shortens the braking distance. during a corner, the sensors detects which wheel is losing grip and the correlatory thruster fires upwards, generating additional downforce on that portion of the vehicle thereby improving overall grip. the car's external would have to undergo major works to accomodate the multi directional firing of the thrusters, but the overall savings in weight could be significant as compared to using all those hydraulics and stuff! so, waddaya think ppl? (i'm talking cock again )
i'd rather stick to the movable aero devices. -
anyway, for u all, u forget that weight takes a toil when there is insufficient downforce. now if such a system was installed in a car, the downforce generated during braking would not only be enough to counter the increased mass, it would even allow the car to have a much shorter braking distance than a much lighter car.