It’s happened again… we have failed to keep posting updates in a timely manner. Many apologies. I’ll try to catch us up a bit:
On the control side, there was a huge amount of progress in April. The system is a huge challenge to control. Keep in mind that in the testing below, we are moving at roughly the maximum speed allowed by our electric lab pumps. When running off the real HPU, the leg can move about twice the speed.
On the mechanical front, final leg design and FEA is in progress. Many of the shortcomings of the prototype leg are being addressed, including: Continue reading →
Our biggest update from this week is that we’ve just been sponsored by Tompkins Industries! Literally 15 seconds before we were about to place a giant order for hoses and fittings to finish our power unit, Tompkins Industries showed up and asked how they can help. Tompkins is a global suppliers of hydraulic adapters and fittings (among many other components) with 99% same-day fulfillment from stock, and are the perfect partners to work with for this phase of the project. Thanks Tompkins!
We worked with Tompkins Industries to get hydraulic fittings and hoses in-house to complete the power unit, and spent our week doing hydraulic assembly. In this update, we’ll show you our progress so far, explain a little bit more about the hydraulic system, and teach you how to assemble hydraulic fittings into a working system. Check it all out here:
Next week, we’ll be working on finishing some modifications to the structure of the power unit to attach batteries, accumulator mounting brackets, and lift points, and we’ll also be testing the prototype leg with the new orifice-reduction fittings James mentioned in his last post. We’re now waiting on some specialty hydraulic parts to finish off the power unit, but once those parts arrive, we’ll be ready to test the unit for the first time!
I’m going to detail a subtle problem we hinted at a few months ago. To understand the problem one needs a basic understanding of the system layout and a few key concepts, so I will quickly review.
Man, what a week! After much toil and effort, the Torchmate 2 computer-controlled plasma cutter is up and running. We’re now putting it through its paces, setting accelerations correctly, tuning cutting power, and figuring out how to transfer files through the two or three pieces of software that control the unit. In the next week, we’ll be adding water to our home-built water table in order to reduce the smoke and particulates and give us cleaner cuts.
We also continued working on the control systems for the leg and the hydraulic power unit. In order to develop code faster, we went ahead and concentrated on updating our simulation to reflect the mechanical realities of the leg – specifically, we added backlash and quirky valve response to the simulation, in the hopes that we can iterate much faster on the control system at home (instead of on-robot). James will have a long, in-depth control systems update soon about this.
The hydraulic power unit is coming along – we’ve mounted all our components, and we’re now working on connecting them together. This week, we’ll show you some of the mounting and fitting assembly work we’ve been doing, and we’re going to take the time to step you all through how the hydraulic power unit works. Let us know if anything was unclear!
Tune in next week for more work on the power unit, and updates on some interesting control systems we’ve been working on to address our mechanical and hydraulic issues on the prototype leg.
This update took us a little longer to get out than usual. We had hoped to finish building a computer-controlled plasma cutter and present it to you all in one update but unfortunately, the manufacturer didn’t ship us all the parts we needed to finish the thing. Oops. We’ll now be getting back to our regularly-scheduled once-a-week updates.
In this update, we cover the building of a Torchmate 2 computer-controlled plasma cutter with a custom-built water table, the continuing development of the hydraulic power unit, and continued testing and debugging of the prototype leg. Check it all out here:
This coming week we’ll be working a lot more on the powerplant – we have a hydraulic heat exchanger coming in that we need to mount (and that we’ll talk more about), and we’ll be starting work on connecting all of our components hydraulically. We’ll also continue development work on the leg, and figure out what courses of action (both mechanically and in control system development) we need to take to reduce the leg judder that you see in many of our videos.
It’s time for the weekly update! The big news this week is that we finally got the prototype leg under closed-loop control – woohoo! We also continued work on the hydraulic power unit frame, made spacers for the powertrain, and started the final round of design on the chassis and leg based on lessons learned from the prototype leg. Check it all out in the video below:
In this coming week, we’ll be doing a lot of tuning of the control loops that govern the leg’s motion, continuing the final design process for the legs, and pushing ahead with the hydraulic power unit integration. Stay tuned – we’re starting to pick up some serious speed!
In our previous update, we mentioned that we had to switch columns within Artisan’s Asylum. We didn’t mention HOW we switched columns. We’d like to take a moment to amuse you with the rather ridiculous, 20-30 minute process we used to get a stuck base mount off the column… set to the Benny Hill theme.
We have come to realize that a) we are bad at this continuing-to-write-blog-posts thing, and b) even so, we really need to be documenting this process for the world to see. Thus, we’ve decided to change gears a bit and offer weekly video updates instead of blog posts. Check out our first update below!
Let us know what you think, and if you have anything you’d like to learn more about!
Just a quick update to announce that all swag (t-shirts, bumper stickers, wrist bands) bound for US addresses has shipped or will ship by end of today. For US supporters – your shirts and bumper stickers should arrive before Christmas.
Here are a few pictures of the team packing up the thousand+ orders. Our deal with the shipping company fell through, so we finally just decided to get everything done the old fashioned way…
International swag has not yet shipped and we’ll let you know when that goes out. We will definitely be shipping international orders before Christmas, but I wouldn’t count on them arriving before Christmas.
