#### Animated Asynchronous Electric Motor Model in Excel

This is an animation of an asynchronous electric motor in Microsoft Excel. You can download the model by clicking on the icon below and try to run it.

#### A Legacy Animated Planetary Model – video preview

A preview of a legacy planetary model.

#### Longitudinal Aircraft Dynamics #11 – full 360 degree operation – aerobatics, inverted flight and loops – FINAL

This section updates an angle formula so that the virtual glider can now perform both backward and forward loops, as well as inverted flight.

#### Longitudinal Aircraft Dynamics #10 – implementing the numerical method

This section of the turorial finalizes the main dynamics calculations and implements the numerical method for approximating the glider trajectory. At this point, the model is already functional but with a crude interface.

#### Longitudinal Aircraft Dynamics #9 – more about forces and momenta – preliminary validation and testing

This tutorial finalizes the implementation of the forces and momenta acting on the plane. It also initiates some hand testing and validation of the overall dynamics of the plane.

#### Longitudinal Aircraft Dynamics #8 – worksheet implementation of the dynamics equations (c)

This section continues the worksheet implementation of the dynamics formulas for aerodynamic forces and momenta.

#### Longitudinal Aircraft Dynamics #7 – worksheet implementation of the dynamics equations (b)

This section continues the  worksheet implementation of the dynamics formulas.

#### Longitudinal Aircraft Dynamics #6 – worksheet implementation of the dynamics equations (a)

In this section, the parameters cl, cd and cm are scaled back to the force of lift, drag and the pitching moment of the aircraft. After that, the numerical  modeling scheme is described together with the macros behind it. At the end, the formulas for the angles of attack of the wing and the horizontal stabilizer are introduced.

#### Animated Heat Transfer Modeling for the Average Joe – part #3

This section shows how to model heat transfer in a linear bar by dividing it in elementary sections in which the basic linear equations introduced in the previous tutorials can be used.

#### How to Model a Phase-Locked Loop (PLL) in Excel – part#1

A Phase-Locked Loop is a type of electronic circuit. It generates an oscillation with the same frequency as a reference oscillation and a relatively constant phase difference  with respect to the same reference. The applications spectrum of such a circuit are extremely wide. Signal modulation, demodulation, detection and filtering, frequency conversion and synthesis are just a fraction of what this circuit can do. Though very simple, it is often not enough understood in industry by…

#### 2D Projectile Motion Tutorial #5

This is the next in a series of projectile motion tutorials for creating 2D trajectory models using numerical analysis of projectile dynamics (including aerodynamic drag). The trajectory formulas were derived in the previous tutorial. This post describes the Excel implementation (spreadsheet formulas, VBA code, buttons and charts).

#### 2D Projectile Motion Tutorial #4

This tutorial derives the formulas of a projectile model taking into account the aerodynamic drag. A finite differences numerical method is used. Though fairly easy to apply and understand, this type of methods can solve much more complex problems than the high-school type approach shown in the previous tutorials. An Excel model will be implemented in the next section.

#### 2D Projectile Motion Tutorial #3

Now that we have a simple animated projectile motion (previous tutorial) let’s try to add on the chart the three instantaneous speed vectors associated with the projectile. These speed vectors are: the horizontal speed, vertical speed and the total speed vector. The model works in all Excel versions but in 2007 it’s painfully slow.

#### 2D Projectile Motion Tutorial #2

This part of the tutorial shows you how to animate the model created in the first part. Since it is addressed to beginners, this part of the tutorial will show you in detail how to create buttons and the associated macros for the input data interface and it will also show you how to animate the flight of the projectile and explain the VBA macro behind the animation.

#### 2D Projectile Motion Tutorial #1

This part of the tutorial will show you how to create the simplest possible projectile motion model using standard kinematic formulas from the first year of high school. The variable parameters of the model will be: initial height, initial speed and initial angle and time step. “g” – the gravitational constant will be set at 9.81 m/s^2. This model is a static one and it will be animated in the following…

#### 2D Projectile Motion Model #1 – a virtual tactical shooting range

Hi Folks, As a kid was fascinated with high power rifles, sniper rifles, cannons and in general, fast projectiles. As a kid I’ve been brainwashed with all sorts of urban legends about how far an AK 47 or a pistol can shoot or how thick a steel metal plate a bullet can penetrate at various distances. I’ve also watched some documentary about snipers and there were talking about highly bent trajectories, how…

#### A basic 3-body Planetary System

Hi folks, as a continuation to the previous tutorial here is a 3-body planetary model where the solution to the equations is contained in a static form, as a lookup table (I previously called it a “pure spreadsheet solution”). The model is static in the sense that after any parameter is changed, the solution data remains unchanged in a table until a new parameter is updated by the user. The display is dynamic however since an “Offset()” function…

#### How to Model a Basic 2-body Planetary System

Here is a tutorial explaining how to model a two dimensional  2-body planetary system in Excel. It uses the Euler method of integration. The tutorial starts with explaining the simple newtonial laws acting on the two planets. There are essentially just two forces acting on each body at any time: the inertia and the gravitational attraction. During each small time step, from the distance between bodies we can calculate the gravitational…

#### 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 elemetary to undersand, try to go through the proof regardless of your background. Recommending this site to your friends would be highly appreciated.   Thanks for your support!

#### 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 elemetary to undersand, try to go through the proof regardless of your background. Recommending this site to your friends would be highly appreciated.   Thanks for your support!