JamD
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I don't get to talk about these things much so always fun for me to geek out as wellThe geek in me is loving these. Could you please give me a 'teacher's explanation' of the simulation? I've been looking for books to help me get started on the flight dynamics of guided rockets/missiles, but i haven't found anything, courtesy of ITAR probably.
An overview of the governing equations used here would be most helpful.
I've assumed:
1. Spherical, nonrotating Earth
2. Newtonian central gravity ( F = GmM/r^2 acting towards center of spherical Earth)
3. Drag as q*S*Cd acting axially (no lift)
4. Cd computed using ballpark Beta values
5. Beta = Weight/(S*Cd)
6. Weight, S, guesstimated to compute beta, which gives you Cd.
7. Standard atmosphere used for density in q.
8. I am starting my simulation at burnout: where the rocket has reached it's maximum speed after burning all of its fuel. I'm assuming this is at 100km. This makes simulations much easier (constant mass).
Then using vector dynamics I derived EOMs in terms of altitude h and angular displacement theta. I am also computing speed V and flight-path angle gamma for analysis. Next, I simulated on MATLAB using ode45 with a termination condition when altitude reaches 10km. I also had the code spit out the data at h = 100 km.
If you are really interested I can do the derivation of the EOMs on latex and post it here. The stuff I've seen online is rather confusing.
Also, I'm attaching the code for you to mess around with and have fun
EDIT: The updated file includes a derivation of the EOMs. Enjoy!
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