Although the widespread use of 3D printers has made things like linear bearings and leadscrews more common, you still can’t run down to your local big-box hardware store and get them. However, you can get drawer slides and any hobby shop can sell you some RC servos. That and an Arduino can make a simple and easy plotter. Just ask [JimRD]. You can also watch it do its thing in the video below.
Of course, servos aren’t usually what you use in a plotter. But the slides convert the rotation of the servo into linear motion. One servo for X and one for Y is all you need. Another microservo lifts the pen up and down using a hinge you could also get from a hardware store.
Is it pretty? No. Does it do amazing artwork? No, again. But it is the kind of thing you could probably throw together from things you happen to have hanging around, especially if you are about to trash an old desk or cabinet with slides in it.
This would make a great rainy day project. We are suckers for simple plotter projects even though you could just mate a pen to your 3D printer or CNC machine. Those won’t fit your whiteboard, though.
Tesla is well known for making cars that can accelerate quickly, but there’s always room for improvement. [Warped Perception] decided that his Tesla Model S P85D needed that little bit of extra oomph (despite the 0-60 MPH or 0-97 km/h time of 3.1 seconds), so he did what any sensible person would: add three jet turbines to the back of his car.
The best part of this particular build is the engineering and fabrication that made this happen. With over 200 pieces and almost all personally fabricated, this is a whirlwind of a build. The control panel is first, and there’s a particularly clever technique of 3D printing the lettering directly onto the control panel for the flat stuff. Then for the pieces with angles that would prevent the head from moving freely, he printed onto a plastic sheet in reverse, applied glue, then stuck the letters to the plate as a sheet. A top layer of clear coat ensures the letters won’t come off later.
He installed the control electronics in the trunk with wiring strung from the car’s front to the rear. Three Arduinos serve as controllers for the jets. Afterward, came the bracket to hold the engines and attach it to the car’s underside. Unfortunately, supplies were a little hard to come by, so he had to make do with what was on hand. As a result it didn’t come out as strong as he would have hoped, but it’s still pretty impressive.
[Warped Perception] does a few tests before taking it out on the road. Then, he shifted the car into neutral and could drive the car solely on jet power, which was one of his goals. While we don’t love the idea of testing a jet engine on public roads, it certainly would discourage tailgaters.
Next, he finds a quieter road and does some speed tests. Unfortunately, it was drizzling, and the pavement was damp, putting a damper on his 0-60 standing times. Electric-only he gets 4.38 seconds, and turning on the jets plus electric shaves that down to 3.32 seconds. Overall, an incredible build that’s sure to draw a few curious glances whenever you’re out on the town.
Although a little smaller than its real-world counterpart, the bright yellow housing and illuminated indicators on this pedestrian lamp are instantly recognizable due to their ubiquitous use throughout the United States. The handful of printed parts are held together using friction alone, which makes assembly a literal snap. The ‘safety grill’ with its many angles ended up being one of the most tedious parts of the build process, but the effort was definitely justified, as it just wouldn’t look right without it.
A suitably minuscule ATtiny85 drives a pair of LED strips that effectively mimic the familiar symbols for ‘Walk’ and ‘Don’t Walk’. [sjm4306] has designed the board and case in such a way to accommodate a variety of options. For example, there’s just enough room to squeeze in a thin battery, should you want to power this contraption on-the-go. If you don’t have an ATtiny85 on hand, the board also supports an ATmega328p or even an ESP8266.
So your ally was slain. Your comrade has fallen. And somehow, that capital F coming from that tiny key is supposed to convey your respect? Please. What you need is a giant, dedicated F key that matches the size of your respect. And [Jaryd_Giesen] is gonna teach you how to build your own. Well, kind of. Between the Thingiverse build guide and the hilarious build video below, you’ll get the gist.
One of the coolest things about this build is the custom spring. Between a birthday time crunch and lockdown, there was just no way to source a giant spring in two days, so [Jaryd] printed a cylinder with a hole in it to chuck into a drill and stand in for a lathe. Ten attempts later, and the perfect spring was in there somewhere.
We love the level of detail here — making a pudding-style keycap to match the main keyboard is the icing on this clacky cake. But the best part is hidden away inside: the stem of the giant switch actuates a regular-sized key switch because it’s funnier that way. Since it’s a giant Gateron red, it doesn’t exactly clack, but it doesn’t sound linear, either, mostly because you can hear the printed pieces rubbing together. Check out the build video after the break, and hit up the second video if you just want to hear the thing.
A 3D printer is a wonderful invention, but it needs maintenance like every machine that runs for long hours. [Rob Ward] had a well-used Robox 3D printer that was in need of some repairs, but getting the necessary replacement parts shipped to Australia was cost-prohibitive. Rather than see a beloved printer be scrapped as e-waste, he decided to rebuild it using components that he could more easily source. Unfortunately the proprietary software and design of the Robox made this a bit difficult, so it was decided a brain transplant was the best path forward.
Step one was to deduce how the motors worked. A spare RAMPS 1.4 board and Arduino Mega2560 made short work of the limit switches and XYZ motors. This was largely accomplished by splicing into the PCBs themselves. The Bowden filament driver motor had a filament detector and an optical travel sensor that required a bit of extra tuning, but now the challenging task was next: extruding.
With a cheap CR10 hot end from an online auction house, [Rob] began modifying the filament feed to feed in a different direction than the Robox was designed for (the filament comes in at a 90-degree angle on the stock Robox). A fan was needed to cool the filament feed line. Initial results were mixed with lots of blockages and clogs in the filament. A better hot end and a machined aluminum bracket for a smoother path made more reliable prints.
The original bed heater was an excellent heater but it was a 240 VAC heater. Reluctant to having high voltages running through his hacked system, he switched them out for 12 VDC adhesive pads. A MOSFET and MOSFET buffer allowed the bed to reach a temperature workable for PLA. [Rob] upgraded to a GT2560 running Marlin 2.x.x.
With a reliable machine, [Rob] stepped back to admire his work. However, the conversion to the feed being perpendicular to the bed surface had reduced his overall build height. With some modeling in OpenSCAD and some clever use of a standard silicone sock, he had a solution that fed the wire into the back of the hot end, allowing to reclaim some of the build height.
It was a long twelves months of work but the write-up is a joy to read. He’s included STL and SCAD files for the replacement parts on the printer. If you’re interested in seeing more machines rebuilt, why not take a look at this knitting machine gifted with a new brain.
3D printers are an excellent tool to have on hand, largely because they can print other tools and parts rapidly without needing to have them machined or custom-ordered. 3D printers have dropped in price as well, so it’s possible to have a fairly capable machine in your own home for only a few hundred dollars. With that being said, there are some limitations to their function but some of them can be mitigated by placing the printer head on a robot arm rather than on a traditional fixed frame.
The experimental 3D printer at the University of Nottingham adds a six-axis robotic arm to their printer head, which allows for a few interesting enhancements. Since the printer head can print in any direction, it allows material to be laid down in ways which enhance the strength of the material by ensuring the printed surface is always correctly positioned with respect to new material from the printer head. Compared to traditional 3D printers which can only print on a single plane, this method also allows for carbon fiber-reinforced prints since the printer head can follow non-planar paths.
Ever wanted your own gesture-controlled robot arm? [EbenKouao]’s DIY Arduino Robot Arm project covers all the bases involved, but even if a robot arm isn’t your jam, his project has plenty to learn from. Every part is carefully explained, complete with source code and a list of required hardware. This approach to documenting a project is great because it not only makes it easy to replicate the results, but it makes it simple to remix, modify, and reuse separate pieces as a reference for other work.
[EbenKouao] uses a 3D-printable robotic gripper, base, and arm design as the foundation of his build. Hobby servos and a single NEMA 17 stepper take care of the moving, and the wiring and motor driving is all carefully explained. Gesture control is done by wearing an articulated glove upon which is mounted flex sensors and MPU6050 accelerometers. These sensors detect the wearer’s movements and turn them into motion commands, which in turn get sent wirelessly from the glove to the robotic arm with HC-05 Bluetooth modules. We really dig [EbenKouao]’s idea of mounting the glove sensors to this slick 3D-printed articulated gauntlet frame, but using a regular glove would work, too. The latest version of the Arduino code can be found on the project’s GitHub repository.
Most of the parts can be 3D printed, how every part works together is carefully explained, and all of the hardware is easily sourced online, making this a very accessible project. Check out the full tutorial video and demonstration, embedded below.
This cool little ziplining robot is courtesy of the folks over at [Tart Robotics]. As they described it, the robot moves using a 4-bar linkage mechanism with the motor’s torque “transferred to the arm mechanisms through a pair of bevel gears and a worm drive.” Even cooler, the robot is activated by clapping. The faster you clap, the faster the robot moves. That’s sure to wow your friends at your next virtual hacker meetup.
They had to do a bit of custom 3D printing work to get a few of the Lego components to connect with their non-Lego off-the-shelf bits, so that took a bit of time. Specifically, they had some cheap, non-branded DC motors that they used that did not naturally mate with the Lego Technic components used to create the rest of the robot’s body. Nothing a few custom 3D printing jobs couldn’t solve.
3D printers have become a staple in most makerspaces these days, enabling hackers to rapidly produce simple mechanical prototypes without the need for a dedicated machine shop. We’ve seen many creative 3D designs here on Hackaday and [jegatheesan.soundarapandian’s] Baby MIT Cheetah Robot is no exception. You’ve undoubtedly seen MIT’s cheetah robot. Well, [jegatheesan’s] hack takes a personal spin on the cheetah robot and his results are pretty cool.
The body of the robot is 3D printed making it easy to customize the design and replace broken parts as you go. The legs are designed in a five-bar linkage with two servo motors controlling each of the four legs. An additional servo motor is used to rotate an HC-SR04, a popular ultrasonic distance sensor, used in the autonomous mode’s obstacle avoidance mechanism. The robot can also be controlled over Bluetooth using an app [jegatheesan] developed in MIT App Inventor.
Overall, the mechanics could use a bit of work — [jegatheesan’s] baby cheetah probably won’t outpace MIT’s robot any time soon — but it’s a cool hack and we’re looking forward to a version 3. Maybe the cheetah would make a cool companion bot?
Robotics projects are always a favorite for hackers. Being able to almost literally bring your project to life evokes a special kind of joy that really drives our wildest imaginations. We imagine this is one of the inspirations for the boom in interactive technologies that are flooding the market these days. Well, [Technovation] had the same thought and decided to build a fully articulated robotic biped.
Each leg has pivot points at the foot, knee, and hip, mimicking the articulation of the human leg. To control the robot’s movements, [Technovation] uses inverse kinematics, a method of calculating join movements rather than explicitly programming them. The user inputs the end coordinates of each foot, as opposed to each individual joint angle, and a special function outputs the joint angles necessary to reach each end coordinate. This part of the software is well commented and worth your time to dig into.
In case you want to change the height of the robot or its stride length, [Technovation] provides a few global constants in the firmware that will automatically adjust the calculations to fit the new robot’s dimensions. Of all the various aspects of this project, the detailed write-up impressed us the most. The robot was designed in Fusion 360 and the parts were 3D printed allowing for maximum design flexibility for the next hacker.
Maybe [Technovation’s] biped will help resurrect the social robot craze. Until then, happy hacking.