stuff made here

9 Articles

Automate Handwritten Postcards With Robots

May 29, 2023 by 15 Comments

As someone notorious for not doing things the old-fashioned manual way, we’re not sure by [Shane] of Stuff Made Here was thinking when he promised to send out a few hundred handwritten letters. Predictably he built an automated production line for the task. Video after the break.

With “handwritten” and “automated” not being particularly compatible, [Shane] set out to create a robot to create believable handwritten letters, which is significantly harder than it may seem at first glance. It turns out that turning your handwriting into a font is too consistent to be believable, which led down the rabbit of generated handwriting. [Shane] first spend a ridiculous amount of time trying to implement a machine learning model for the task, only to find there’s already an open source library good enough to fool a forensic handwriting expert.

On the robot side, [Shane] used a pen plotter from Amazon that’s it’s actually cheaper than building one from scratch. With the “handwriting” taken care of, [Shane] set up an automated loading system with the industrial robot arm he also used for his CNC chainsaw. The feeders for the empty and full postcards are 3D printed with a spring-loaded mechanism to keep the top card at the same height all the time.

Although this project contained less custom hardware and software than [Shane’s] other projects, it served as an excellent reminder that it’s unnecessary to reinvent the wheel when building a car. It’s easy to get caught up in the small details of a project that don’t matter much in the final implementation and usage.

Continue reading “Automate Handwritten Postcards With Robots” →

Putting The ‘Go’ In Frisbee Golf With A Robot Launcher

March 6, 2022 by 10 Comments

If you’ve gone to a local city park lately, you might have noticed strange metal baskets on poles with chains dangling free. These baskets are spread out throughout the park seemingly at random. For the uninitiated, Frisbee golf (sometimes known as disc golf) is a confusing concept. You might not think it, but Frisbee golf can be a very big deal to some people. [Stuff Made Here] is back with a disc launcher that he hopes will put all the disc golfers to shame.

It’s no secret that we here at Hackaday are big fans of [Stuff Made Here], or [Shane] (he has his own tag after all), and for obvious reasons — the CAD design process, the careful machining and testing, and the extremely high bar that [Shane] sets for his projects. This one is no different, and it is a tale of iteration and scaling. He started out with a simple goal: break the speed record for a thrown Frisbee.

An initial design was decided upon based on high-pressure air pushing a piston to throw the Frisbee off of an arm. Initially, the arm was way too slow as the airflow was severely restricted due to air solenoids and pressure regulators. After fixing all those problems by fabricating his own solenoid and adding a secondary tank with no regulator, the arm started really moving. However, [Shane] wanted it to be able to be arm-mounted, so making sure the torque wouldn’t melt his arm bones was an important priority.

A counterbalance was added to cancel it out, but that ended up causing additional problems down the road, so the throwing arm had to be made as light as possible. The gripper mechanism had to be redesigned again and again as each time the speed was increased, a new problem arose. Turns out that small plastic discs being accelerated at many G’s tend to deform and slip out of their holders, no matter how well engineered. So [Shane] switched to a clever new design to pull the Frisbee along rather than push. It was too dangerous to really be handheld, and the only tests while he was wearing it were at very low amounts of pressure and power.

Testing it in a wide-open field at full power showed promise and while he had plenty of speed, he wasn’t able to beat the distance record. Breaking the distance record is much harder as Frisbees aren’t really designed with the sheer acceleration that [Shane] is subjecting them to, and they want to flip. Additionally, the Frisbees are lacking the spin that would keep them more stable, and what we do as humans is quite difficult to reproduce. Maybe a larger-scale version of this disc launcher could be made that accepts Frisbees?

It’s incredible to watch this contraption come together as each part needs to be designed and machined first by [Shane]. Video after the break.

Continue reading “Putting The ‘Go’ In Frisbee Golf With A Robot Launcher” →

Building An Archery Mech Suit To Skip Practice

August 19, 2021 by 8 Comments

According to legend, King Edward III once said: “If you want to train a longbowman, start with his grandfather.” Consistently making accurate hits with any bow, especially on moving targets, takes many hours of practice. Or, if you’re [Shane Wighton], you can spend a comparable amount of time building, debugging, and rebuilding a robotically-enhanced bow to do it.

The goal was to shoot flying targets out of the air, so [Shane] had to create a system that could track the position of the bow and the target, and automatically adjust the position of the bow and loose the arrow at exactly the right moment to intercept the target. The position tracking was done with the same Optitrack cameras [Shane] used on his robotic basketball hoop, with reflective marking balls on the bow, target, and the release mechanism. The auto-aiming is done with a two-axis rack and pinion mechanism driven by a pair of stepper motors. [Shane] first used the cheapest recurve bow he could find online, which caused accuracy issues likely related to the Archer’s paradox. The setup also made him repeatedly hit himself in the face, because the servo-operated release mechanism would release unexpectedly without having a proper anchor with his draw hand.

[Shane] eventually upgraded to a compound bow, which reduced the tension he had to hold while lining up the shot, but also increased the weight of the system dramatically. This leads him to fully embrace the mech suit look, and use a Steadicam vest to hold the weight of the bow. This finally allowed him to reliably William Tell shots and hit the flying targets.

Whether it’s an all-in-one electronic golf club, an explosive baseball bat, or a robotic pool cue, [Shane] is certainly adept at using impressive engineering skills to compensate for his lack of physical skill, or just his willfully closed eyes. Continue reading “Building An Archery Mech Suit To Skip Practice” →

Robotic Pool Cue Can Be Your Friend Or Your Foe

February 24, 2021 by 21 Comments

In his everlasting quest to replace physical skill with technology, [Shane] of [Stuff Made Here] has taken aim at the game of eight-ball pool. Using a combination of computer vision and mechatronics, he created a robotic pool system that can allow a physical game of pool over the internet, or just beat human players. See the video after the break.

Making a good pool shot requires three discrete steps. First, you need to identify the best shot, then figure out how exactly to strike the balls to achieve the desired results, and finally physically execute the shot accurately. [Shane’s] goal was to automate all these steps. For the physical part, he built a pool cue with a robotic tip which only requires the user to place in approximately the right position, while a pneumatic piston mounted on a Stewart platform does the rest. A Stewart platform is a triangular plate mounted with six reciprocating rods, which gives it the required freedom of motion. The rods’ bases are attached to a set of cranks actuated by tension cables pulled by servos mounted at the rear-end of the cue. An adjustable air system allows the power of the shot to be adjusted as required.

A camera mounted is mounted over the table and connected to computer vision software to gather the required position information. Fiducials on the corners of the table and the cue tip allow the position of the pockets, balls, and cue to be accurately determined, and theoretically should allow the robot to take the perfect shot. Getting this to work in reality quickly turned into a very frustrating experience. After many hours of debugging, [Shane] tracked the error to a tiny forgotten test function that was introducing 5-10 mm of position error, and 2 of the six servos in the cue not performing up to spec. To determine the vertical positioning of the cue, an IMU and fixed height foot were added. [Shane] also added an overhead projector to overlay all required information directly on the table. Continue reading “Robotic Pool Cue Can Be Your Friend Or Your Foe” →

Making A “Unpickable” Lock

November 29, 2020 by 51 Comments

Every time manufacturers bring a new “unpickable” lock to market, amateur and professional locksmiths descend on the new product to prove them wrong. [Shane] from [Stuff Made Here] decided to try his hand at designing and building an unpickable lock, and found that particular rabbit hole to be a lot deeper than expected. (Video, embedded below.)

Most common pin tumbler locks can be picked thanks to slightly loose fits of the pins and tiny manufacturing defects. By lifting or bumping the pins while putting tension on the cylinder the pins can be made to bind one by one at the shear line. Once all the pins are bound in the correct position, it can be unlocked.

[Shane]’s design aimed to prevent the pins from being set in unlocked position one by one, by locking the all pins in whatever position they are set and preventing further manipulation when the cylinder is turned to test the combination. In theory this should prevent the person doing the picking from knowing if any of the pins were in the correct position, forcing them to take the difficult and time-consuming approach of simply trying different combinations.

[Shane] is no stranger to challenging projects, and this one was no different. Many of the parts had to be remade multiple times, even with his well-equipped home machine shop. The mechanism that holds the pins in the set position when the cylinder is rotated was especially difficult to get working reliably.  He explicitly states that this lock is purely an educational exercise, and not commercially viable due to its mechanical complexity and difficult machining.

A local locksmith was unsuccessful in picking the lock with the standard techniques, but the real test is still to come. The name [LockPickingLawyer] has probably already come to mind for many readers. [Shane] has been in contact with him and will send him a lock to test after a few more refinements, and we look forward to seeing the results! Continue reading “Making A “Unpickable” Lock” →

Five-Axis Pumpkin Carving

October 29, 2020 by 21 Comments

The day of carved pumpkins is near, and instead of doing manually like a mere mortal, [Shane] of [Stuff Made Here] built a five-axis CNC machine to take over carving duties. (Video, embedded below.)

[Shane] initially intended to modify his barber robot, but ended up with a complete redesign, reusing only the electronics and the large ring bearing in the base. The swiveling spindle is a rotating gantry with two sets of aluminum extrusions for vertical and horizontal motion. The gantry isn’t very rigid, but it’s good enough for pumpkin carving. Software is the most challenging part of the endeavor due to the complexity of five-axis motion and mapping 2D images onto a roughly spherical surface. Cartographers have dealt with this for a long time, so [Shane] turned to Mercator projection to solve the problem. We’re also relieved to hear that we aren’t the only ones who sometimes struggle with equation-heavy Wikipedia pages.

Since there are no perfectly spherical pumpkins, [Shane] wrote a script to probe the surface of the pumpkin with a microswitch before cutting, appropriately named “TSA.exe”. The machine is capable of carving both profiles and variable depth lithophanes, mostly of [Shane]’s long-suffering wife. She seriously deserves an award for holding onto her sense of humor.

With projects like explosive baseball bats and CNC basketball hoop, the [Stuff Made Here] YouTube Channel is worth keeping an eye on.

Going For The Home Run Record With Explosive Help

October 27, 2020 by 6 Comments

The baseball home run distance challenge for crazy engineers is really heating up, with the two main (only?) competitors joining forces. [Shane] of [Stuff Made Here] and [Destin] of [Smarter Every Day] did a deep dive into [Shane]’s latest powder charged baseball bat, designed to hit a ball 600+ feet.

[Shane] built two new versions of his bat this time, using the lessons he learned from his previous V1 and V2 explosive bats. It still uses blank cartridges, but this time the max capacity was increased from three to four cartridges. For V3 a section of the bat was removed, and replaced with a four-bar linkage, which allowed the entire front of the bat to move. The linkage integrated a chamber for four blank cartridges that could be loaded almost like a double barrel shotgun and closed with a satisfying snap. Unfortunately the mass of the moving section was too much for the welds, and the entire front broke off on the first test, so the design was scrapped.

V4 returned to the piston concept of the initial version, except V4 contains two parallel pistons, in a metal bat, with a larger hitting surface. With two cartridges it worked well, but parts started breaking with three and four, and required multiple design updates to fix. [Destin] covered the physics of the project and took some really cool high speed video. He and [Jeremy Fielding] hold the current distance record of 617 ft with their crazy Mad Batter. Unfortunately on [Shane]’s final distance attempt the bat broke again, and the ball was lost in a field with tall grass beyond the 600-foot mark, so they could not confirm if the record was actually broken.

[Destin] and his team still remain the undisputed baseball velocity record holders, with their supersonic baseball canon. It sounds like there might be another collaboration between [Destin] and [Shane] in the future, and we’re definitely looking forward to the results of that crazy venture. Continue reading “Going For The Home Run Record With Explosive Help” →