One of the worst features of the A2 design in my view(appart from not enough space for left foot) is the hard suspension which transfers bumps in the road direct to bumps on the B****. I have been thinking about why clever designers in Audi have not come up with a better solution. I am an Engineer but not a specialist in the dynamics of suspension design so my reasoning might be wrong, but here goes.
The A2 has very low sprung weight by virtue of its aluminium construction. The unsprung weight (i.e. tyres, wheels, brakes, etc ) is fairly standard for this size of car.Hence the ratio of unsprung to sprung weight is high and this is not good for ride comfort. Why, because the unsprung weight needs a hefty force acting through the suspension to keep it in contact with the road when driving fast over uneven surfaces.The light body of the A2 is uncapable of providing the necessary preload in the springs.
For these reasons the A2 suspension also has quite a high natural frequency i.e. the reatio of sprung weight to spring stiffness is low. The Audi designers probably found that to increase ride confort they would have to reduce spring stiffness to the point where changes in sprung weight due to passengers getting in and out, luggage etc, caused an unacceptable change in car trim.
A2 owners may have noticed that the ride quality is greatly improved when carrying passengers. This is because the natural frequency of the sprung mass of the caer is now lower by virtue of the increased sprung mass.
What is the answer? If you want a comfortable ride buy a heavy car: if you want performance and economy buy an A2.
However, I am a little surprised that the Audi designers didnt specify softer seats to take the edfge off the bumpy ride.
The A2 has very low sprung weight by virtue of its aluminium construction. The unsprung weight (i.e. tyres, wheels, brakes, etc ) is fairly standard for this size of car.Hence the ratio of unsprung to sprung weight is high and this is not good for ride comfort. Why, because the unsprung weight needs a hefty force acting through the suspension to keep it in contact with the road when driving fast over uneven surfaces.The light body of the A2 is uncapable of providing the necessary preload in the springs.
For these reasons the A2 suspension also has quite a high natural frequency i.e. the reatio of sprung weight to spring stiffness is low. The Audi designers probably found that to increase ride confort they would have to reduce spring stiffness to the point where changes in sprung weight due to passengers getting in and out, luggage etc, caused an unacceptable change in car trim.
A2 owners may have noticed that the ride quality is greatly improved when carrying passengers. This is because the natural frequency of the sprung mass of the caer is now lower by virtue of the increased sprung mass.
What is the answer? If you want a comfortable ride buy a heavy car: if you want performance and economy buy an A2.
However, I am a little surprised that the Audi designers didnt specify softer seats to take the edfge off the bumpy ride.
