Hi guys i’m having a small project to design a spring powered trebuchet that will be capable of hurling 26 Kg

Hi guys i'm having a small project to design a spring powered trebuchet that will be capable of hurling 26 Kg

stone for a mininum distance of 100 meters. I seriously don’t know what type of springs should i use so that sufficient power is generated and how many springs must they be.

I need help please from any experts.

Yes i do know how to calculate the dimensions of a parabola, those are simple mathematics. Tell me how many springs should i use, is’t tension springs, compression springs or torsional springs?

A Balista will use torsion springs. You can also use compression or extension springs.

The total work from the springs must be the same as total work necessary to lift the rock through the required height to achieve the 100 meter distance. That energy is mgh were h is the height of the parabola.

For a extension or compression spring the energy is 1/2*Kx^2 were K is the spring constant and x is the change in length of the spring.

For a torsion spring there is a similar equation 1/2*K*a^2 where a = the angular displacement spring.

Niel

A trebuchet or more correctly a counter balance trebuchet is a gravity powered device, it does not have springs [1] [2]. There are a number of other catapults which do use spring or other mechanism to store the energy necessary to throw the projectile.

I have a couple of questions for you so maybe we do the calculations together. Do you understand how to calculate the dimensions of a parabola?

The minimum energy trajectory will have a starting angle of 45 degrees. The length between the two end points will be 100 meters. Knowing this information, the acceleration of gravity and the mass of the stone you are throwing you can calculate the minimum energy required to throw the stone 100 meters.

Niel Leon
engineering.com