Driving Sim Handbrake Based On Load Cell

Simulator-style video games are designed to scale in complexity, allowing players to engage at anything from a casual level to highly detailed, realistic simulation. Microsoft Flight Simulator, for example, can be played with a keyboard and mouse, a controller, or a huge, expensive simulator designed to replicate a specific airplane in every detail. Driving simulators are similar, and [CNCDan] has been hard at work on his DIY immersive driving sim rig, with this hand brake as his latest addition.

For this build, [CNCDan] is going with a lever-style handbrake which is common in motorsports like drifting and rallying. He has already built a set of custom pedals, so this design borrows heavily from them. That means that the sensor is a load cell, which takes input force from a lever connected to it with a spring mechanism. The signal is sent to an Arduino for processing, which is set up to send data over USB like any joystick or controller. In this case, he’s using an Arduino that was already handling inputs from his custom shifter, so he only needed to use another input and add some code to get his handbrake added into his sim.

[CNCDan] built a version of this out of laser-cut metal parts, but also has a fully 3D printable one available as well. Plenty of his other videos about his driving rig are available as well, from the pedal assembly we mentioned earlier to the force-feedback steering wheel. It’s an impressive set of hardware with a feel that replicates racing about as faithfully as a simulator could. Interestingly, we’ve also seen this process in reverse as well where a real car was used instead as a video game controller.

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2025 Component Abuse Challenge: Load Cell Anemometer

When you think anemometer, you probably don’t think “load cell” — but (statistically speaking) you probably don’t live in Hurricane Country, which is hard on wind-speed-measuring-whirligigs. When [BLANCHARD Jordan] got tired of replacing professionally-made meteorological eggbeaters, he decided he needed something without moving parts. Whatever he came up with would probably qualify for the Component Abuse Challenge, but the choice of load cells of all things to measure wind speed? Yeah, that’s not what the manufacturer intended them for.

In retrospect, it’s actually a fairly obvious solution: take a plate of known area, and you’re going to get a specific force at a given air speed. The math isn’t hard, it’s just not how we normally see this particular measurement done. Of course, a single plate would have to be pivoted to face the wind for an accurate reading, which means moving parts– something specifically excluded from the design brief. [Jordan] instead uses a pair of load cells, mounted 90 degrees to one another, for his anemometer. One measures the force in a north-south axis, and the other east-west, allowing him to easily calculate both wind speed and direction. In theory, that is. Unfortunately, he vibe coded the math with ChatGPT, and it looks like it doesn’t track direction all that well. The vibe code runs on an ESP32 is responsible for polling data, tossing outliers, and zeroing out the load cells on the regular.

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2025 Pet Hacks Contest: Weigh Your Dog The Easy Way

If you need to weigh your pet, you’ll soon find that getting an animal to stand on a weighing machine to order is very difficult indeed. If the critter in question is a cat or a small dog you can weigh yourself both holding them and not holding them, and compute the difference. But in the case of a full size Bernese mountain dog, the hound is simply too big for that. Lateral thinking is required, and that’s how [Saren Tasciyan] came up with the idea of making a dog bed that’s also a weighing machine. When the mutt settles down, the weight can be read with ease. The bed itself is a relatively straightforward wooden frame, with load cells placed above rubber feet. The load cells in turn talk to an ESP8266 which has an LCD display to deliver the verdict. Dog weighed, without the drama.

This project is of course part of the Hackaday 2025 Pet Hacks contest, an arena in which any of the cool hacks you’ve made to enhance you and your pet’s life together can have an airing. Meanwhile this isn’t the first time this particular pooch has had a starring role; he’s sported a rather fetching barrel in a previous post.

RC Car Gets Force Feedback Steering

Remote-controlled cars can get incredibly fast and complex (and expensive) the farther into the hobby you get. So much so that a lot of things that are missing from the experience of driving a real car start to make a meaningful impact. [Indeterminate Design] has a few cars like this which are so fast that it becomes difficult to react to their behavior fast enough through sight alone. To help solve this problem and bridge the gap between the experience of driving a real car and an RC one, he’s added force feedback steering to the car’s remote control.

The first thing to tackle is the data throughput required to get a system like this working wirelessly. Relying heavily on the two cores in each of a pair of ESP32s, along with a long-range, high-speed wireless communications protocol called ESP-NOW, enough data from the car can be sent to make this possible but it does rely on precise timing to avoid jitter in the steering wheel. Some filtering is required as well, but with the small size of everything in this build it’s also a challenge not to filter out all of the important high-frequency forces. With the code written, [Indeterminate Design] turned to the 3D printer to build the prototype controller with built-in motors to provide the haptic feedback.

The other half of the project involves sensing the forces in the RC car which will then get sent back to the remote. After experimenting with a mathematical model to avoid having to source expensive parts and finding himself at a deadend with that method, eventually a bi-directional load cell was placed inside the steering mechanism which solved this problem. With all of these pieces working together, [Indeterminate Design] has a working force feedback steering mechanism which allows him to feel bumps, understeer, and other sensations, especially while doing things like drifting or driving through grass, that would be otherwise unavailable to drivers of RC cars. The only thing we could think of to bring this even more into realistic simulation territory would be to add something like a first-person view like high-speed drones often have.

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Coffee Grinder Gets Bluetooth Weighing

Some people take their coffee grinding seriously. So what do you do when the hot new grinders automatically weigh coffee, and yours doesn’t? Well, if you are like [Tech Dregs] and the rest of us, you hack your existing grinder, of course. The link is to the source code, but for a quick overview, check out the video below.

In true hacker fashion, the first order of business was to pull a load cell out of a cheap scale. Originally, he intended to reuse the processor inside, too, but it was epoxied, so it was a good excuse to use some more modules. A load cell amplifier, an OLED display, and a tiny Xiao processor, which he describes as “ridiculous.” From the context, we think he means ridiculously small in the physical sense and ridiculously powerful for such a tiny board.

With the modules, the wiring wasn’t too hard, but you still need some kind of app. Thanks to App Inventor, an Android app was a matter of gluing some blocks together in a GUI. Of course, the devil is in the details, and it took a lot of “focused cursing” to get everything working correctly.

The coffee grinder has a relay to turn the motor on and off, so that’s the point the scale needs to turn the motor on and off. Conveniently, the grinder’s PCB had an unpopulated pin header for just this purpose.

This is one of those simple projects you can use daily if you drink coffee. We are always impressed that the infrastructure exists today and that you can throw something like this together in very little time without much trouble.

WiFi hacking coffee makers is a popular Java project in these parts. Upgrading a machine can get pretty serious with PID control loops and more.

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Cheap Kitchen Scale Learns To Speak JSON With ESP32

Smart kitchen appliances are expensive, and more often than not, your usage data goes to whichever company operates the inevitable cloud service. Meanwhile the cheap ones contain substantially the same components without the smarts, so surely a hardware hacker can add a microcontroller to a cheap appliance for a bit of smart home technology without the privacy issues? It’s something [Liore] has done with an Amazon Basics kitchen scale, removing the electronics and wiring up an ESP32 to the load cell instead.

The Wheatstone bridge load cell circuit generates a tiny voltage difference that’s far too small for an ESP32 to measure, so in between the pair is an Avia Semiconductor HX711 strain gauge amplifier module. In addition, there’s a small OLED screen and the two buttons used in the Amazon scale are wired in too, providing the the kitchen scale functionality you’d expect.

Naturally the ESP32 brings along with it WiFi networking capabilities, which [Liore] has taken full advantage of here. By navigating a web browser to its IP address, you’ll receive the scale’s current reading in JSON format. This should make it easy to integrate with other systems, from Home Assistant to OctoPrint. We can see that there is plenty of scope for further enhancements for those prepared to write a little code.

Of course, this isn’t the first enhanced scale we’ve brought you, here’s one with Bluetooth. We’ve also seen hackers dispense with the kitchen-safe trappings and build the load cell directly into their own contraptions.

A repair stand for bicycles with an integrated scale

DIY Repair Stand Holds Your Bike And Weighs It

If you’ve ever done maintenance or repair work on your bicycle, you’ll know that positioning a bike in your workshop isn’t trivial. You can use your bike’s kickstand, or lean it against a wall, but then you can’t work on the wheels. You can place it upside-down, but then the shifters and brake levers are hard to reach. You can hang it from the ceiling, but then you first need to install hooks and cables in hard-to-reach places. Ideally you’d want to have one of those standing clamp systems that the pros use, but their price is typically beyond a hobbyist’s budget.

Or at least, that’s how it used to be. As [Dane Kouttron] discovered, a simple wall-mounted bike clamp can be had for as little as $35 on eBay, and can easily be converted into a smart mobile repair stand. [Dane] fashioned an adjustable stand from some steel pipes he had lying around, and 3D-printed an adapter bracket to mount the bike clamp on it. This worked fine, but why stop at a simple clamp when you can expand it with, say, an integrated scale to weigh your bikes while you work on them? Continue reading “DIY Repair Stand Holds Your Bike And Weighs It”