VTOL Tailsitter Flies With Quadcopter Control Software

Quadcopters are great for maneuverability and slow, stable flight, but it comes at the cost of efficiency. [Peter Ryseck]’s Mini QBIT quadrotor biplane brings in some of the efficiency of fixed-wing flight, without all the complexity usually associated with VTOL aircraft.

The Mini QBIT is just a 3″ mini quadcopter with a pair of wings mounted below the motors, turning it into a “tailsitter” VTOL aircraft. The wings and nosecone attach to the 3D printed frame using magnets, which allows them to pop off in a crash. There is no need for control surfaces on the wings since all the required control is done by the motors. The QBIT is based on a research project [Peter] was involved in at the University of Maryland. The 2017 paper states that the test aircraft used 68% less power in forward flight than hovering.

(Editor’s Note: [Peter] contacted us directly, and he’s got a newer paper about the aircraft.)

Getting the flight controller to do smooth transitions from hover to forward flight can be quite tricky, but the QBIT does this using a normal quadcopter flight controller running Betaflight. The quadcopter hovers in self-leveling mode (angle mode) and switches to acro mode for forward flight. However, as the drone pitches over for forward flight, the roll axis becomes the yaw axis and the yaw axis becomes the reversed roll axis. To compensate for this, the controller set up to swap these two channels at the flip of a switch. For FPV flying, the QBIT uses two cameras for the two different modes, each with its own on-screen display (OSD). The flight controller is configured to use the same mode switch to change the camera feed and OSD.

[Peter] is selling the parts and STL files for V2 on his website, but you can download the V1 files for free. However, the control setup is really the defining feature of this project, and can be implemented by anyone on their own builds.

For another simple VTOL project, check out [Nicholas Rehm]’s F-35 which runs on his dRehmFlight flight control software. Continue reading “VTOL Tailsitter Flies With Quadcopter Control Software”

Home Depot Is Selling Power Tools That Require Activation In-Store

Shoplifting is a major problem for many brick-and-mortar retail stores, and it seems that stealing and then selling power tools is a lucrative enterprise for some criminals. To combat this, Home Depot is starting to sell power tools that will not work unless they are activated at the checkout counter.

According to a 2020 survey in the US, “organized retail crime” cost retailers $719,548 per $1 billion dollars in revenue. One thief was recently arrested after stealing more than $17,000 worth of power tools from Home Depot. While many stores put high value items in locked display cases, Home Depot felt that this tactic would negatively affect sales, so they partnered with suppliers to add an internal kill switch. Although persistent criminals might find a way to deactivate this feature, it sounds like Home Depot is hoping that will be just enough trouble to convince most criminals to look for easier targets somewhere else.

We would be really interested in getting our hands on one of these power tools to see what this kill switch looks like and how it works. Something like a Bluetooth activated relay is one option, or maybe even something that is integrated directly in the motor controller. If it were up to us, we would probably pick something that receives power wirelessly using a coil and requires a unique code. For their sake, we hope it’s not something that can be deactivated with just a large magnet.

Thanks for the tip [Garth Bock]!

Create Large Scale Domino Art With A Robot

Creating large domino art displays is a long and nerve-racking process, where bumping a single domino can mean starting from scratch. To automate the process of creating these displays, a team consisting of [Mark Rober], [John Luke], [Josh], and [Alex Baucom] built the Dominator, a robot capable of laying 100 000 dominos just over 24 hours. Video after the break.

[Mark Rober] had been toying with the idea for a few years, and the project finally for off the ground after [Mark] mentioned it in a talk he gave at the 2019 Bay Area Maker Faire. To pull it off, the team created an entire domino laying system, including an automated loading station, a precision indoor positioning system, and the robot itself. The robot is built around a frame of aluminum extrusions, riding on three omnidirectional wheels driven by precision servo motors. A large tray mounted to the front of the robot can hold and release 300 dominos at a time. The primary controller is a Raspberry Pi 4, which receives positioning information from a Marvelmind indoor positioning system and a downward-facing IR camera that looks for reflective markers on the floor. The loading system uses a conveyor system to feed the different colored dominos to an industrial Kuka robot that drops them down a grid of tubes that can hold multiple layers at once.

Continue reading “Create Large Scale Domino Art With A Robot”

Tabletop Basketball With Tentacles

Unlike football/soccer and foosball, basketball doesn’t really lend itself to being turned into a tabletop game quite that easily. [The Q] has found a way around that, employing tentacle mechanisms to create a two-player, basketball-like game.

Each player uses a pair of two-axis control sticks and a foot pedal to operate a cable-driven tentacle with a gripper on the end. These are two stage tentacles, meaning that the top and bottom halves are independently controlled. The tentacles consist of a series of laminated foam discs clued onto bicycle cable sleeves. The cables are open in the section they control, and operate in a push-pull arrangement. The spring-loaded grippers are operated by the foot pedals, with a single cable running down the center of the tentacle.

The game looks quite fun and challenging, and we can imagine it being even more entertaining with teams of two or three people operating each tentacle. Add a bit of alcohol to adult players, and it might become downright hilarious, although the mechanisms would need to be beefed up a bit to survive that level of punishment.

We suspect [The Q] read [Joshua Vasquez]’s incredibly detailed three-part guide on two-stage tentacle mechanisms. Combine that with his guide to cable mechanism math, and you’d be well-equipped to build your own. Continue reading “Tabletop Basketball With Tentacles”

Get Some Close Air Support With A Nerf Drone

Working from home has the major advantage of spending more time with loved ones, but it all that time can sometimes lead to friction. [Cory] found that Nerf battles with his kids is an effective way to blow off some steam, but felt he was getting a bit too much exercise in the process. Instead, he equipped an FPV quadcopter with a 3D printed Nerf gun to take his place.

Since manually reloading the Nerf gun after every shot wasn’t an option, he needed to create an autoloader. The darts are propelled by a pair of brushless drone motors mounted side-by-side, with just enough space for a dart the squeeze between. The motors are allowed to spin up, and then a dart is loaded servo-operated plunger, out of an off-the-shelf Nerf magazine. The motors ESCs and servo is controlled by an Arduino Nano, which receives the fire command from one of the spare outputs on the drone’s flight controller. To nerf gear is easily removable from the drone, so [Cory] to also fly the drone on more peaceful missions. See the video of one of the battles after the break. [Cory] might need to find an alternative control location to prevent himself being used as cover by his adversaries.

Nerf guns are a fun and harmless way to live out your sci-fi warfare fantasies, especially with the technology we have available these days. From FPV sentry guns to auto-aiming rifles, and heavy artillery, anything is possible.

Continue reading “Get Some Close Air Support With A Nerf Drone”

Monowheel Balancing Robot Can’t Turn (Yet)

Self-balancing robots have become a common hobby project, and they usually require two wheels to work. [James Bruton] has managed to single wheel balancing robot by adding gyroscopic stabilization.

[James] has done other self-balancing robots, like his Sonic robot, but recently started experimenting with gyroscopic stabilization. In that project, he proposed the idea of combining the two stabilization methods to create a monowheel robot, and he followed through on that idea. The wheel is powered by a brushless motor and is stabilized conventionally around the wheel’s axis. Side to side balancing is achieved using a phenomenon known as gyroscopic precession, by tilting a pair of heavy spinning wheels. This is not to be confused with reaction wheels, which use rotational inertia for control. It appears the actuating the gyroscopes also affects the front-to-back stabilization, so at the moment the robots won’t stay on one spot. [James] plans to implement a second observation controller in software to solve this.

Another challenge with this robot is that it cannot turn at the moment. The gyroscopes are not in the correct orientation to effect rotation around the vertical axis, and changing their orientation would cause other problems. A fan, which works like a helicopter’s tail rotor is one option, and a reaction wheel on top might also work. We’re partial to the reaction wheel idea. Having a different mechanical control mechanism for each axis would make it quite an interesting robot.

Continue reading “Monowheel Balancing Robot Can’t Turn (Yet)”

Avoid Awkward Video Conference Situations With PIR And Arduino

Working from home with regular video meetings has its challenges, especially if you add kids to the mix. To help avoid embarrassing situations, [Charitha Jayaweera] created Present!, a USB device to automatically turn of your camera and microphone if you suddenly need to leave your computer to maintain domestic order.

Present consists of just a PIR sensor and Arduino in a 3D printed enclosure to snap onto your monitor. When the PIR sensor no longer detects someone in range, it sends a notification over serial to a python script running on the PC to switch off the camera and microphone on Zoom (or another app). It can optionally turn these back on when you are seated again. The cheap HC-SR501 PIR module’s range can also be adjusted with a trimpot for your specific scenario. It should also be possible to shrink the device to the size of the PIR module, with a small custom PCB or one of the many tiny Arduino compatible dev boards.

For quick manual muting, check out the giant 3D printed mute button. Present was an entry into the Work from Home Challenge, part of the 2021 Hackaday Prize.