Hi guys, here is the first part of a tutorial describing the mathematical equations used in modeling a three-pendulum harmonograph (automatic drawing machine). It pertains to the second version of the model. This section refers only to the kinematic equations for the movement of three pendulums. A second section will be published later and it will describe the kinematic equations involved inContinue Reading

Hi! Here is an improved (faster and cleaner) version of the harmonograph. The worksheet has three different areas, the physical machine (a photo of the machine build out of wood by Karl Sims), the virtual machine (which is a 2D chart with a top view of a model showing the three pendulum ends, the drawing table, and the linkage mechanism which connects pendulum #1,Continue Reading

There are many available built-in spreadsheet functions in Excel. Occasionally one might need a very special custom function. This short tutorial is an introduction about how to write a user defined function which calculate the distance between two points in a Cartesian plane. The topic will be continued and custom functions will occasionally be used in future models. We’d loveContinue Reading

Hi guys, here is the final part of tutorial about creating a digital clock in Excel. It is a good tutorial about general use of sprites in animation, especially the first half. Tell us your thoughts, George [sociallocker][/sociallocker] Building an Digital Clock in Excel – part #2 – a full digital clock model using the “digit” sprites by George LunguContinue Reading

Hi there, this is a better version of Pong, in which you play with a virtual opponent. It does not have a score board yet and the opponent is theoretically unbeatable. I will be improving it further. Excel 2007 is quite slow on this one. In order to get maximum speed out of Excel 2007 make sure you zoom in as much asContinue Reading

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 theContinue Reading

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 Newtonian 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,Continue Reading

Here is a speedometer in Excel 2003. It’s an old file and the charting wasn’t done in the most economic fashion. I used too many series while I could have consolidated a lot of the dial curves. It is still a good example of animation and displaying custom numbers on a chart. There are two VBA macros involved, one for changingContinue Reading

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 visualizeContinue Reading