When making a toy excavator arm, or any robotic arm, the typical approach is to put motors at the joints, or if there isn’t room, to put the motors somewhere else and transfer the force using fishing line and pulleys. [Navin Khambhala] chose instead to do it more like the real excavators, with hydraulics using syringes. And we have to admit, the result it pretty elegant in its simplicity.
The syringes do the job of single-acting hydraulic actuators, one at the motor and the other where the force is needed. In between them, what appears to be clear vinyl tubes carry the fluid between syringes. 12 volt DC motors with bolts on them move nuts attached to the syringe pistons to push and pull the pistons. It is so simple that no further explanation is needed, though like most apparently simple things, we’re sure a lot of effort went into making it that way. The video below shows the finished product, as well as walks through the making of it.
Continue reading “Super Simple Hydraulics Using Syringes”
[Frank] was lucky enough to score a bucket wheel excavator LEGO set as a birthday present, and we won’t lie – we’re jealous. However, out of the box, the kit is somewhat limited; there is only one motor to animate the entire machine and it can’t be fully remote controlled. But don’t worry — [Frank] set out to change that (Google Translation).
The first part of the build was to add motors to control the different functions of the excavator. One motor was added for each of the two tracks to allow the machine to drive forwards, backwards, and turn. Two more motors were added to raise and lower the digging buckets, and spin the tower. Finally, the original motor was left in place to turn the conveyor.
With that done, [Frank] then used a Raspberry Pi 3 to control all the hardware, being sure to house the new electronics in LEGO for an original look. The Raspberry Pi might be a lot of muscle to simply control a few motors, but it made it quick and easy for [Frank] to implement a Wiimote as a controller over Bluetooth. You can check out a couple demo videos in his most recent update.
It’s a great project, and we’d love to see the Raspberry Pi put to good use by allowing control over the Internet so we can dig in the sand over lunch breaks. We’ve seen some great LEGO hacks before, like this method of modifying cheap gear motors to work with LEGO parts.
You’ve just got to go with the hype on this one, because it’s obviously not ready for prime time yet. But a few days ago murmurs started circling the net that an Australian inventor had developed a robot capable of building complicated structure from brick all by itself.
Before you go off your rocker… we’re definitely not calling this real. It’s a proof of concept at best, but that doesn’t prevent us from getting excited. How long have you been waiting for robots that can build entire structures on our behalf? We were excited at the prospect of extruding walls of concrete. But this is more like LEGO buildings in the real world. The beast cuts brick to length, conveys each brick along the telescoping arm, and butters them as it lays them in place. At least that’s what the rendered video after the break shows.
We’re hearing about this now because FastBrick Robotics, the company [Mark Pivac] founded and has spent ten years developing the Hadrian project at, was just sold to a company called DMY Capital Limited. Of course they’re going to want to get some press out of the sale.
There is an image of the brick feeder on an existing excavator that frankly looks photoshopped. And some real images like the one seen here and another of the “print head” holding some bricks. But it’s enough to think there’s potential here.
The idea is that the base of the robot is fixed with the arm long enough to reach any part of the structure being built. Precise positioning is achieved by a fixed marker in a different position from the robot. The head triangulates its position using laser range-finding with the marker (having said that we now assume there needs to be more than one marker).
So what do you think? Are we ever going to see this incredibly complicated bucket of awesome producing structures in our neighborhood which the Big Bad Wolf simply cannot blow down?
Continue reading “Hope it’s real: 3D Printing Houses with Bricks”