Pulling Firing Pin

[Dr.Gusta]

Okay so after some discussion on CD on another thread my team and I feel like we are pretty close to nailing down a design. The big issue we have right now is being able to pull the pin when there is large forces pulling on it. Let me. Try and explain what our plan is. We are going to have a Claw pick up and hold the ball. A surgical tubing "sling shot" will be pulled back by a pneumatic piston. We want to fire the "sling shot" by pulling the pin on the linkage between the surgical tubing and the piston. The issue is we are going to try and get 50-60lbs worth of force when the surgical tubing is pulled back. That is going to make it next to impossible. What my question is, is there any special linkage that can be easily pulled even though it is pulled on by large forces. Thank you for any help you can provide.