If you’re building a robot for off-road or rough terrain, chances are you’ve thought about using a tank-tread style drive. There are a ton of kits available with plastic tread and wheels, but they are typically really expensive or pretty flimsy. Instead of going with an off-the-shelf solution, [Paul B] designed a heavy-duty tank tread made with common bike chain and conduit.
Some DIY tread designs we’ve featured just use a single bike chain on either side of the tread pieces. This gets the job done, but each section of tread is usually bolted through the chain. This means that you can’t use a sprocket to drive the chain since all the bolt heads block where the teeth engage. Instead, these designs typically use drive wheels inside the tread, which are prone to slip under a heavy load. [Paul B]’s design is a bit different: it uses a DIY double-wide chain so he can bolt tread segments to the chain and still use a drive sprocket.
Constructing the double-wide chain took quite a bit of work. [Paul B] completely disassembled a couple of bike chains with a delinker tool and then reassembled the chain in a double-wide configuration with M3 bolts instead of the original chain pins. Each section of tread (made out of cut pieces of plastic conduit) bolts on the outside section of chain, and a sprocket runs on the inside. His DIY chain approach saves him money too, since double-wide chains are pretty expensive. Since his sprockets directly engage the drive train, his design should be able to handle as much torque as his drivetrain can put out.
There are just somethings you don’t see often when it comes to motorcycles, 2 wheel drive and tank tracks. Well, [jeep2003] has combined both those oddities into one project he calls the Track-Powered 2×2 MiniBike.
As his descriptive project name suggests, this minibike has tracks instead of wheels. The track assemblies originally came off a snow blower. As if just having tracks wasn’t difficult enough, both sets are powered. The back has a straight forward chain and sprocket setup while the front ads in a clever jack-shaft and universal joint contraption which is shown in the video after the break around the 3:08 mark.
[jeep2003] doesn’t say where the tubing for his custom made frame came from, but from the photos available it appears they were once old bicycle frames. The powerplant is a 6.75hp vertical shaft Briggs & Stratton engine. The output shaft connects to a Peerless 5 speed transmission that also has reverse. This transmission usually outputs to two rear drive wheels of a riding lawnmower. [jeep2003] dedicates each axle output from the transmission to power one of the two track systems.
Although this minibike won’t be breaking any land speed records anytime soon, we here at HaD still think it’s a pretty rad build.
Continue reading “Tank Track Motorcycle Goes Anywhere, Slowly”
[Michael] sells a remote control spy tank through his company, and although it’s a toy, there’s an impressive amount of electronics in this R/C tank. It’s controlled from an Android or iDevice over a WiFi connection, something that simply won’t do if you’re trying to sell this to the hacker and maker crowd. The solution to this problem is Wireshark, and with a little bit of work this spy tank can be controlled from just about anything, from a microcontroller via WiFi to a Python app.
Wireshark, everyone’s favorite network packet analysis and capture tool, was used to listen in on the communications between an iPad and the tank. This immediately showed the video stream coming from the camera in the tank, and pointing VLC to the correct port displayed the video.
The motors in the tank were a little trickier, but looking at the data stream, a few packets stood out as being responsible for controlling the motors. After a little experimentation the simple command set was decoded and a Python app whipped up.
These spy tanks are cheap – about $70 from [Michael]’s company and the other usual vendors. It’s not a particularly useful piece of hardware, but someone out there is sure to do something cool with this bit of reverse engineering.
What do you get when you cross 7 hobby gearboxes with 14 wheels and a LiPo battery? Instead of speculating an answer, we can just check out one of [rctestflight’s] projects.
He came across those hobby gearboxes and thought it would be fun to build a 14 wheel drive contraption. Each gearbox has its own motor and is wrapped up in a nice tidy package also including the axle and wheels. All of the wheels mounted on a straight board wouldn’t be much fun so [rctestflight] used heavy duty zip ties that act as a flexible frame to connect one gearbox to the next. This allows the vehicle to bend and climb over obstacles while keeping as many wheels in contact with the ground as possible.
All 7 motors are powered by a single cell LiPo battery. In the video after the break it appears the vehicle can steer or that it is remotely controlled, but that is not the case. Once the battery is plugged in it just goes forward. This isn’t the first time one of [rctestflight’s] projects has been featured on Hackaday, check out his Free Falling Quadcopter Experiment.
Continue reading “14 Wheel Drive Vehicle Climbs Over Most Things”
Throughout the 1950s and early 1960s, the United States Army provided regular status reports to both its interior members and the American public through a half-hour documentary television show called The Big Picture. Since the program was produced by the government, every episode immediately entered the public domain. This particular report tells the story of the T-48 project that culminated in the 90mm M48 Patton tank.
The film opens by providing a brief history of tanks and the lessons learned about them between WWI and the Korean War. The Army sought a more robust vehicle that could handle a wide variety of climates and terrain, and so the process of information gathering began. After a series of meetings at the Pentagon in which all parties involved explored every facet, the project was approved, and a manila folder was officially designated to the project and labeled accordingly.
We then tour the R&D facility where new tank materials and components are developed and tested. It is here that the drive gears are put through their paces on a torsion machine. Air cleaners are pitted against each other to decide which can filter out the finest dust and sand. After careful analysis, different tank shell materials are test welded together with various, well-documented electrodes, and these panels are taken outside so their welds can be directly fired upon.
Continue reading “Retrotechtacular: The (Long, Arduous) Birth of a Tank”
When we hear reports of radioactive water leaking into the ocean from the [Fukushima Dai-Ichi] plant in Japan we literally have to keep ourselves from grinding our teeth. Surly the world contains enough brain power to overcome these hazards. Instead of letting it gnaw at him, [Akiba] is directing his skills at one solution that could help with the issue. There are a number of storage tanks on site which hold radioactive water and are prone to leaking. After hearing that they are checked manually each day, with no automated level monitoring, he got to work. Above is the wireless non-contact tank level sensor rig he built to test out his idea.
A couple of things made this a quick project for him. First off, he just happened to have a MaxSonar MB7389 waterproof sonar sensor on hand. Think of this as a really fancy PING sensor that is water tight and can measure distance up to five meters. [Akiba’s] assumption is that the tanks have a hatch at the top into which this sensor would be positioned. The box next to it contains a Freakduino of his own design which includes hardware for wireless communications at 900 MHz. This is the same hardware he used for that wireless toilet monitor.
We really like seeing hacker solutions to environmental problems. A prime example is some of the cleanup hacks we saw around the time of the BP Gulf of Mexico oil spill.
The tank robot builds that we see are often quite complex. This lets them do great things, but makes the platform scary for beginners. Here’s a tank build that would be a great first project, especially if you’re more interested in the programming side of robotics than you are in the hardware itself. [Paul Bleisch] combined several different commercially available products to fabricate this Arduino-powered tank robot base.
Locomotion is provided by a double geared-motor module. This unit, the plastic wheels and treads, as well as the wooden mounting platform are all made by Tamiya. They cost very little and are already designed to work with one another. To this base he adds the Arduino and a motor shield which makes the connections dead simple. The black case on one end of the chassis holds four AA batteries which provide power for everything.
These components are all that’s really needed to start, but they provide no interactivity. So [Paul] picked up a used wireless PlayStation 2 controller. There’s a library (written by regular reader [Bill Porter]) that allows him to connect the receiver to the Arduino in order to pick up commands from the controller. He also plans to add an ultrasonic range finder to the build sometime in the future.
If you’re don’t need to do things the easy way you should consider fabricating your own tank treads.