Tools and Code

Here is a list of some of the tools and programs/codes that I have developed for vehicle sizing, design and experimental analysis. Email me for questions!

Design Build Fly : Fixed Wing Sizing

This excel sheet is the perfect first order analysis tool for building a model RC airplane. The design derives from mission requirements which are payload and total endurance (doesn't assume a flight profile). The design is not-iterative in nature but allows for iteration based on endurance and AUW convergence. Weight buildup is based on foam-board (prefilled density that is changeable) and not balsa as I find foamboard easier to work with. The sizing code accounts for Roll, Yaw and Pitch stability based on usual/acceptable values of stability margins and volume coefficients. Damping coeffecients are not considered here. The Prop-sizing code has been copied from Gabriel Staples empirical work on Propeller sizing. The code assits in calculation of the optimal motor, propeller diameter and pitch, battery requirement and size of each control surface and componenent to meet the mission requirements and maintain static stability in all three axes.

Dropbox link to Excel Sheet

Design Build Fly : Multicopter Sizing

This excel sheet is the perfect first order analysis tool for building a multicopter RC drone. The design derives from mission requirements which are # of rotors, payload capacity, Hover endurance and Propeller diameter. The design code assumes a generic mass breakdown and Thurst to Weight ratio based on published empirical formulations for quadcopters in the same weight class. The design is non-iterative in nature but allows for easy iteration based on endurance and AUW convergence. The code doesn't account for vehicle stability criterions. While the code assists in calculation of optimal Propeller diameter and pitch and motor kV and power loading, it does depend on the user to find suitable commercial motors that meet the criterions.

Dropbox link to Excel Sheet

Atmospheric Acoustic Attenuation

This MATLAB code solves for the atmospheric attenuation between two points in space. The code is based on Sutherlands 19773 model of attenuation and follows ASA S1.26. The code also allows for "mean atmosphere" values of pressure and temperature as a function of geopotential altitude to calculate attenuation at altitude. Additionally, the code also provides error bounds for calculated attenuation values based on known empirical attenuation coefficients.

Dropbox link to MATLAB code

Two-Microphone Method

The two microphone method is a popular standardized technoque for determining the normal aoustic impedance of materials. In this method, an acoustic river is mounted at one end of an acoustic waveguide, and the test speciimen is mounted at the other.Two microphones are flush mounted in the duct wall to determine the incident and reflected waves. The microphone data is used to estimate the complex reflection coefficient and the corresponding acoustic impedance of the test specimen. Correlation component of this code was written by Shane Lympany.

Dropbox link to MATLAB code

Rotor Acoustics

With the advent of electric VTOL concepts, acoustics becomes an important design criterion for vehicle designers.To faciliate VTOL activies in urban environments, designers will have to incoporate noise dampening technologies to reduce the acoustic footprint of their vehicles. This excel sheet gives a quick SPL vs Frequency plot for the given rotor and thrust loading parameters. The code models both narrowaband rotor rotational noise at harmonics of BPF and broadband vortex noise at higher frequencies.

Dropbox link to Excel Sheet