Here is the first part of a casual tutorial in both elementary dynamics and numerical methods. It is written at a very basic level and it shows you how to solve a system of difference equations with a pencil and a paper and perhaps a pocket calculator to speed things up. A casual approach to numerical modeling – the Spring-Mass-Damper-System –… Read More... "Casual Introduction to Numerical Methods – a spring-mass-damper system model – part#1"

This category hosts engineering animated models in MS Excel. Excel is particularly valuable in engineering being inexpensive and ubiquitous. In my career I managed to solve difficult engineering problems by building animated simulations where engineers using other, much more expensive software, failed. Unlike dedicated engineering software, excel is not a “black box”, which means that you develop your models from scratch using basic principles, calculations and charting. This leads to a much better understanding and control of the problem.

Excel is a great software for engineering calculations because it can combine data tables, charts and even engineering formulas under the same application.As far as civil engineering is concerned, Excel can do regular calculations such as cost estimates, schedule and cost control, and markup estimation, as well as structural calculations of reactions, stresses, strains, deflections, and slopes. Excel can deal with difficult problems, charting, and report generation.

## Instant 3D-2D Perspective Mapping – the Navigator Functions – a convenient pair of user defined functions

This tutorial explains a pair of important user defined functions, the “Navigator_u()” and the “Navigator_v()”. These functions save the user nine columns of formulas by calculating the effects of: 3-dimensional shift, rotations around the three axes of coordinates and 3D-2D perspective mapping. These user defined functions are also easy to use compared to writing all the perspective mapping equations from… Read More... "Instant 3D-2D Perspective Mapping – the Navigator Functions – a convenient pair of user defined functions"

## 3D-2D Perspective Mapping in Excel – part #2

The first half of this presentation dealt with mapping a 3D scene onto a 2D surface which can be a computer screen, a projection screen or the retina of the eye. By doing so we preserve much of the feel of depth of the scene. Of course when we look at an picture we get only part of the feel… Read More... "3D-2D Perspective Mapping in Excel – part #2"

## 3D-2D Perspective Mapping in Excel – part #1

In computer graphics we often need to be able to display a three-dimensional image in two dimensions and preserve the perspective appearance. If we walk on a straight road, it appears that the road narrows with the distance. This is the perspective effect and it is a result of mapping a three-dimensional image on a two-dimensional surface (i.e. a computer… Read More... "3D-2D Perspective Mapping in Excel – part #1"

## Tutorial – a Static Lissajous Emulator

Hi there, this is a tutorial explaining the construction of a very basic Lissajous emulator in Excel. It’s supposed to be very easy to understand at the high school level. Good luck, George [sociallocker][/sociallocker] A Lissajous emulator in Excel by George Lungu Introduction: Jules A. Lissajous was a French mathematician from the 19th century – He wanted to visualize… Read More... "Tutorial – a Static Lissajous Emulator"

## Introduction to Numerical Methods – Basic Filters #2

This post shows the steps for building a first model of a single pole RC high pass filter (HPF) in Excel based on numerical solution using the finite difference method. It is quite elementary to understand, try to go through the proof regardless of your background. [sociallocker][/sociallocker] Basic Filters – Part 2 (1-Pole High Pass Filter) Numerical Solutions to Differential Equations… Read More... "Introduction to Numerical Methods – Basic Filters #2"

## Introduction to Numerical Methods – Basic Filters #1

This post shows the steps for building a first model of a single pole RC low pass filter (LPF) in Excel based on numerical solution using the finite difference method. It is quite easy to understand, try to go through the proof regardless of your background. [sociallocker][/sociallocker] Basic Filters – Part 1 (1-Pole Low Pass Filter) – Numerical Solutions to Differential Equations (Finite Difference… Read More... "Introduction to Numerical Methods – Basic Filters #1"

## Dynamic Lissajous Emulator

This is a dynamic Lissajous emulator in the sense that the waveform is obtained by combining 2 time varying sinusoidal waves with different frequencies. [sociallocker][/sociallocker] Read More... "Dynamic Lissajous Emulator"

## Static Lissajous Emulators (2D and 3D)

This is a static Lissajous emulator in the sense that the waveform is obtained by combining 2 static sinusoidal waves with different frequencies. As a parenthesis, I will be preparing a dynamic version which will look just like the wave shape seen on a real oscilloscope. The file presented here has two different worksheets, the first one contains a classic 2D… Read More... "Static Lissajous Emulators (2D and 3D)"

## Triple Spring-Mass-Damper System

This is the model of a triple spring-mass-damper system in excel. [sociallocker][/sociallocker] Read More... "Triple Spring-Mass-Damper System"

## Double Spring-Mass-Damper System

This is an animated model of a double spring-mass-damper system in excel. [sociallocker][/sociallocker] Read More... "Double Spring-Mass-Damper System"

## Simple Spring-Mass-Damper System

This is the model of a simple spring-mass-damper system in excel. [sociallocker][/sociallocker] Read More... "Simple Spring-Mass-Damper System"

## Phase Lock Loop (PLL)

This is an Excel workbook containing a dynamic model of a Phase Lock Loop. [sociallocker][/sociallocker] Read More... "Phase Lock Loop (PLL)"

## Fourier Transform

This is an Excel workbook calculating the Fourier transform of a signal. [sociallocker][/sociallocker] Read More... "Fourier Transform"