antiroll bar 4 myvi

share about ARB

fact n myth
let's bust the myth

aku tak faham kenape UR ARB dipanggil ARB.
aku rase fungsi dia tak ubah macam lower arm bar....
sape2 komen la....

Principles
A sway bar is usually a torsion spring that resists body roll motions. It is usually constructed out of a U-shaped piece of steel that connects to the body at two points, and at the left and right sides of the suspension. If the left and right wheels move together, the bar just rotates about its mounting points and does not bend. If the wheels move relative to each other, the bar is subjected to torsion and forced to twist.

The bar resists the torsion through its stiffness. The stiffness of an anti-roll bar is based on the fourth power of its diameter, the stiffness of the material, the inverse of the length of the lever arms (i.e., the shorter the lever arm, the stiffer the bar), the geometry of the mounting points, and the rigidity of the bar's mounting points. Some anti-roll bars, particularly those intended for use in auto racing, are adjustable, allowing their stiffness to be altered by increasing or reducing the length of the lever arms. This permits the roll stiffness to be tuned for different situations without replacing the entire bar. The stiffer the bar, the more force required to move the left and right wheels relative to each other. This increases the amount of force required to make the body roll.

In a turn, the sprung mass of the vehicle's body produces a lateral force at the center of mass, proportional to lateral acceleration. Because the cg is usually not on the roll axis, the lateral force creates a moment about the roll axis that tends to roll the body. (The roll axis is a line that joins the front and rear roll centers (SAEJ670e). The moment is called the roll couple.

Roll couple is resisted by the suspension roll stiffness, which is a function of the spring rate of the vehicle's springs and of the anti-roll bars, if any. The use of anti-roll bars allows designers to reduce roll without making the suspension's springs stiffer in the vertical plane, which allows improved body control with less compromise of ride quality.

One effect of body (frame) lean, for typical suspension geometry, is positive camber of the wheels on the outside of the turn and negative on the inside, which reduces their cornering grip (especially with cross ply tires).


Anti-roll bars provide two main functions:
The first function is the reduction of body lean. The reduction of body lean is dependent on the total roll stiffness of the vehicle. Increasing the total roll stiffness of a vehicle does not change the steady state total load (weight) transfer from the inside wheels to the outside wheels, it only reduces body lean. The total lateral load transfer is determined by the CG height and track width.

The other function of anti roll bars is to tune the high g-force / limit understeer behavior of the vehicle. The limit understeer behavior is tuned by changing the proportion of the total roll stiffness that comes from the front and rear axles. Increasing the proportion of roll stiffness at the front will increase the proportion of the total weight transfer that the front axle reacts and decrease the proportion that the rear axle reacts. This will cause the outer front wheel to run at a higher slip angle, and the outer rear wheel to run at a lower slip angle, which is an understeer effect. Increasing the proportion of roll stiffness at the rear axle will have the opposite effect and decrease understeer.

then why the UR ARB not connected to the body? why only connect to the torsion beam like their lower arm bar? this thing still made me pening2 lalat la...

Actually the tyre part will make body roll. Thats y they insatlled it there hold the tyre. thats y i was connected to the rear or front suspension part....i will show where when i capture it ok

A stabilizer bar tries to keep the car's body flat by moving force from one side of the body to another. To picture how a stabilizer bar works, imagine a metal rod that is an inch or two (2 to 5 cm) in diameter. If your front tires are 5 feet (1.6 meters) apart, make the rod about 4 feet long. Attach the rod to the frame of the car in front of the front tires, but attach it with bushings in such a way that it can rotate. Now attach arms from the rod to the front suspension member on both sides.

When you go into a turn now, the front suspension member of the outside of the turn gets pushed upward. The arm of the sway bar gets pushed upward, and this applies torsion to the rod. The torsion them moves the arm at the other end of the rod, and this causes the suspension on the other side of the car to compress as well. The car's body tends to stay flat in the turn.

If you don't have a stabilizer bar, you tend to have a lot of trouble with body roll in a turn. If you have too much stabilizer bar, you tend to lose independence between the suspension members on both sides of the car. When one wheel hits a bump, the stabilizer bar transmits the bump to the other side of the car as well, which is not what you want. The ideal is to find a setting that reduces body roll but does not hurt the independence of the tires.

taken from : http://auto.howstuffworks.com/question432.htm

ok. i understand it's theory but,

what i want to say here is,
many of us buy the ARB but they didn't know how it work, they just know the ARB reduce body roll but they didn't know the concept of the ARB.

ok.

our rear suspension is a torsion beam, both tyre are connected. it's connected by a strait bar.
(same like the honda fit/jazz).
not like the wira,vios or evo.

for example i like to talk about the UR ARB, as we already know, the UR ARB tie up to both tyre but not to the chasis. so for me it much like the lower arm bar. i know how the torsion beam work but i still wonder why the D-Sport develop their own ARB that tie up to the torsion beam and chasis?and if u see the other brand like D-pro and 3-max, they ARB was connect to the chasis.

then, when we take a left connering, for example, right suspension will be compressed and on the left suspension will decompressed, mean weigh(berat) of the car will tranfered to the rigth suspension and tyre. thats why our body will feel like want to go to right side. then if we put the ARB, the ARB will reduce compressed spring, that means the ARB will tranfer chasis weigh(berat) to both side. this will keep car's body flat as heikalsan said.

then if ARB work like that, how the UR ARB can reduce the compression if the ARB connect only to torsion beam and not to the chasis? for me, there's nothing can hold the car body from rolling accept just the suspension. then why should we put the ARB if it can't work as the theory?

hehehe sorry i'm bad in english, i didnt mean to condem someone.

actually its depend to their research man....Maybe.....they will provide their own type of it....and maybe all of the bars dependency each other.. and maybe y they didnt tight to chasis?? becoz when accident you will see how is your car...would be...

yeah dude, but if xcdent..... huhuhu so sad

yups.
dats rite bro.
just installed d UR ARB,
but cant see d relevan of dat tak elok mencarut... holding torsion beam.
its already has a big beam to hold both tires.
adoilaa......

maybe we've been conned by UR!