[HELP] Tank Width

[oracid]

What is the best tank's width ?

As you know, I am interested in tank and you can see my tests on this thread, http://www.eurobricks.com/forum/index.php?showtopic=119844

During my tests, I found that the more the tank's width was big, the less the track goes out of his lane during a turn on a spot.

I have the intuition that when the track follows a large circle, the friction caused by ripage is less.

I guess this is because of the shorter distance of the extremities of the track and the perimeter of the circle.

But how to prove it? I will like to make a video on the subject, but I have not done great studies and I'm afraid to say stupid things.

Could someone explain this without too much math?

Thank you in advance.

[syclone]

Well,when larger the space between tracks,larger the circle the do.Lafger the circle, larger the amount of track that provides traction,that means that the tracks practically go straight

I hope you understand me,and I have a correct theory

Also I think that the motors need less torque to do that

Edited April 3, 2016 by LXF

[MajorAlvega]

Well,when larger the space between tracks,larger the circle the do.Lafger the circle, larger the amount of track that provides traction,that means that the tracks practically go straight

So it's not quite just tank length but the tank area?

Also I think that the motors need less torque to do that

That would explain something that has been puzzling me: Oracid tank uses 4 XL motors and a PF LiPo battery that never clips current. I use smaller tank with just 2 XL motors but when using PF AA battery box with good batteries it clips whenever I force the tank to much.

There are other differences in our tanks (mostly suspension) but width seems to be main one.

[sonar]

The width of any tank is determined by the turret ring in my opinion. If you examine real tanks you could see from the moment the Main Battle Tank concept was developed, every tank uses the hull as wide as the turret ring allows. This is always a balancing act from tank development perspective: the breech of the main gun increases the size of the turret ring the higher caliber of the gun goes, the smallest frontal profile is desired which is achieved by decreasing the turret ring.

If you plan on adding turret with mechanisms inside it, I would suggest taking into account the space between tracks these mechanisms will take when turning the turret.

I'd suggest examining Kelkschiz Mark 6 Autoloader Tank to see the modern real life tank development concepts applied using Lego.

[Kelkschiz]

I think you should take into consideration that it's not width so much but the relation between length and width. Because a theoretical tank of any width will have minimal friction when the length is close to zero. I hope you can follow my reasoning. So from the perspective of turning it would be more appropriate to talk about the ideal length. However length is interesting for other reasons as well, as you have shown with you climbing videos ;). But as Sonar pointed out a tank's width is usually dominated by the diameter of it's turret ring.

@sonar, thanks for the mention :)

Edited April 3, 2016 by Kelkschiz

[oracid]

Thanks a lot for your answers.

As far as I understand, my intuition was therefore good. For a tank with an imposed length, to reduce friction of the track, it is best to do the widest possible.

By reading you, I realize that I forgot to mention that my tank is rather intended to robotic base. I doubt that for a tank, climbing stairs is a problem.

Nevertheless, I must carefully consider the problem of the turret which in my case would be dedicated to an articulated arm, for example.

It remains for me to explain it in a video with very few words...