Loads Analysis

Owned by Roman Kobets
Last updated: Oct 30, 2022
1 min read

Executive Summary

A primary goal of any rocket structure is to ensure it can withstand the loads the rocket will experience through flight.

[WIP]

 

Existing Loads Analysis Method @ Waterloo Rocketry

Primarily pioneered by Shirley Kong & Reasoning documented Here

BENDIT7 is a calculator built in excel by Charles Houlthttp://www.rsandt.com/reports.html#StruLoad. Accompanying it is a report explaining the mathematical models that describe loading in a sounding rocket.

To generate load cases that are useful for our teams' rocket design, certain approximations or modifications are made. Those will be outlined here and can be found throughout Shirley's design document.

The process to come up with loads (for 2022 KOTS, Cycle 1 2023 KOTS+ loads), is roughly outlined:

  1. Rocket design is broken into distinct sections, usually per what is convenient for mass estimates or assemby points.

  2. The rocket flight is simulated to obtain following parameters at liftoff and MaxQ:

    1. Altitude

    2. Speed

    3. Cg

    4. Cp

    5. [more]

  3. All of the fields on the 'inputs' tab are filled in based on data from flight simulations, design parameters, and CAD. Certain approximations or assumptions are made.

As it is set up, the google docs “Loads Analysis” spreadsheet mostly serves for documentation purposes, and minimal calculations are actually run there. The BENDIT7 spreadsheet, complete with Macros, is what actually computes the calculations, based on inputs listed in the google sheets.

4. The inputs are copied into the BENDIT7 calculator