Ah, I see.
No, I haven't.
The spear's displacement is all in the X direction since it sits on a rail mounted on top of the barrel. Any component of force in the downward Y direction is negated by this.
This would however cause frictional drag between the rail and the spear. Which I hadn't...
I have separated the resultant force from the bands into the X and Y components to account for losses due to the bands not being aligned with the axial direction of the spear... If that's what you mean.
Thanks!
I'll have a play around with it. Seems like it could be quite a neat solution.
I had previously looked at using known ballistics data (G1 Reference Bullet) to calculate the coefficient of drag, but what I am modelling seemed so far removed from the experimental data I'm not sure how...
Yep, fair point.
The project is an analysis of speargun performance.
The experiment was to measure the initial velocity of a spear as it leaves a speargun. Using slow motion video footage I have measured this velocity.
The theoretical calculation is based on the length and extension of rubber...
About to graduate in the field of Mechanical Engineering. My final year dissertation project is an analysis of speargun performance. If you need assistance on speargun set up, I'm the guy to talk to.
Jacob
I have two values for the initial velocity of a projectile through water. One is measured experimentally and the other a theoretical value for initial velocity.
The measured value is 23.75m/s
The theoretical value is 26.3m/s Resistance forces were not accounted for in this calculated value.
To...