Finally, the stroke length equation is:

As an example, assume the desired performance of a catapult is:

terminal velocity (vm)=80 ft/sec

maximum rate of change of acceleration ()=150 g/sec

From equations (19), (20), and (21)

The approximate stroke length then is determined from equation (26)

S=6.47 ft or 77.6 in.

velocity-time and travel-time curves are desired, they can be determined by first and second

integrals of the acceleration-time curve.

operating with a constant internal pressure after t1 and designed in accordance with assumptions in

some manner, or if the tube areas are known or related in some manner, by minor changes in

equations (22) through (26).

stroke length should be increased by approximately 10 percent. To reach the desired separation

velocity of 80 fps, the stroke should be approximately 86 inches.

was based on equal tube areas for the inner and telescoping tubes (essentially a two-tube catapult).

The reduction and simplification of equation (26) using a tube area ratio of 1 result in the following

equation:

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