simulator

75 Articles

Experience Other Planets With The Gravity Simulator

July 27, 2025 by 8 Comments

As Earthlings, most of us don’t spend a lot of extra time thinking about the gravity on our home planet. Instead, we go about our days only occasionally dropping things or tripping over furniture but largely attending to other matters of more consequence. When humans visit other worlds, though, there’s a lot more consideration of the gravity and its effects on how humans live and many different ways of training for going to places like the Moon or Mars. This gravity simulator, for example, lets anyone experience what it would be like to balance an object anywhere with different gravity from Earth’s.

The simulator itself largely consists of a row of about 60 NeoPixels, spread out in a line along a length of lightweight PVC pipe. They’re controlled by an Arduino Nano which has a built-in inertial measurement unit, allowing it to sense the angle the pipe is being held at as well as making determinations about its movement. A set of LEDs on the NeoPixel strip is illuminated, which simulates a ball being balanced on this pipe, and motion one way or the other will allow the ball to travel back and forth along its length. With the Earth gravity setting this is fairly intuitive but when the gravity simulation is turned up for heavier planets or turned down for lighter ones the experience changes dramatically. Most of the video explains the math behind determining the effects of a rolling ball in each of these environments, which is worth taking a look at on its own.

While the device obviously can’t change the mass or the force of gravity by pressing a button, it’s a unique way to experience and feel what a small part of existence on another world might be like. With enough budget available there are certainly other ways of providing training for other amounts of gravity like parabolic flights or buoyancy tanks, although one of the other more affordable ways of doing this for laypeople is this low-gravity acrobatic device.

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Semiconductor Simulator Lets You Play IC Designer

May 12, 2025 by 8 Comments

For circuit simulation, we have always been enthralled with the Falstad simulator which is a simple, Spice-like simulator that runs in the browser. [Brandon] has a simulator, too, but it simulates semiconductor devices. With help from [Paul Falstad], that simulator also runs in the browser.

This simulator takes a little thinking and lets you build devices as you might on an IC die. The key is to use the drop-down that initially says “Interact” to select a tool. Then, the drop-down below lets you select what you are drawing, which can be a voltage source, metal, or various materials you find in semiconductor devices, like n-type or a dielectric.

It is a bit tricky, but if you check out the examples first (like this diode), it gets easier. The main page has many examples. You can even build up entire subsystems like a ring oscillator or a DRAM cell.

Designing at this level has its own quirks. For example, in the real world, you think of resistors as something you can use with great precision, and capacitors are often “sloppy.” On an IC substrate, resistors are often the sloppy component. While capacitor values might not be exact, it is very easy to get an extremely precise ratio of two capacitors because the plate size is tightly controlled. This leads to a different mindset than you are used to when designing with discrete components.

Of course, this is just a simulation, so everything can be perfect. If, for some reason, you don’t know about the Falstad simulator, check it out now.

Atomic Clock Trades Receiver For An ESP8266

April 7, 2025 by 20 Comments

The advantage of a radio-controlled clock that receives the time signal from WWVB is that you never have to set it again. Whether it’s a little digital job on your desk, or some big analog wall clock that’s hard to access, they’ll all adjust themselves as necessary to keep perfect time. But what if the receiver conks out on you?

Well, you’d still have a clock. But you’d have to set it manually like some kind of Neanderthal. That wasn’t acceptable to [jim11662418], so after he yanked the misbehaving WWVB receiver from his clock, he decided to replace it with an ESP8266 that could connect to the Internet and get the current time via Network Time Protocol (NTP).

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Next time on Star Trek: EmptyEpsilon... (Credit: EmptyEpsilon project)

Build A Starship Bridge Simulator With EmptyEpsilon

March 23, 2025 by 29 Comments

Who hasn’t dreamed of serving on the bridge of a Star Trek starship? Although the EmptyEpsilon project isn’t adorned with the Universe-famous LCARS user interface, it does provide a comprehensive simulation scenario, in a multiplayer setting. Designed as a LAN or WAN multiplayer game hosted by the server that also serves as the main screen, four to six additional devices are required to handle the non-captain tasks. These include helm, weapons, engineering, science and relay, which includes comms.