This project goes in the “off topic” area since the project was designed/fabricated/tested before I owned the AVIDcnc…
The PDF (link below) is stuffed full of 400+ decent quality images, so it is a little too big to open on most cell phones out there but if you download it to a PC with a decent amount of RAM and a good sized monitor, you might get a kick out of this. Lots of fabrication, Stainless, Aluminum, acrylic, injection molding, electronic design, software, sensor fusion, etc…
PDF project photo gallery, click here
You’ll have to download it and open it locally it’s just a big file.
Don’t you just love it when the finished thing comes out looking like the CAD model? If you looked at the actual implementation in the linked *.PDF file, then you’ll probably understand why, I enjoy working on these robotic projects and so many different aspects of design / fabrication…
For those that aren’t interested in this kinds of stuff, I’ll share this one photo from about 1/2way through the mechanical assembly portion of the project…
That is some robot Ken!! This must have taken hundreds of hours to design/build/test. Only looked at about 1/5 of the pics and will do more later. Maybe my question is answered and I missed it, but what was the purpose of the robot? Now if it could pick/kill dandelions I’d think I had to build one; maybe smaller. Love the project!
what was the purpose of the robot?
@gordo , Most of the other robots I’ve built have had a purpose. Mirosort soccer, Robo-Magellan, Autonomous Circumnavigation of the block that I live on, etc… This is the first one I have built that was meant to be general purpose. Even before it was done I was using several of the systems bolted into the software integration rig (shown in the photos in there) to debug some video processing algorithms. Years back a member of the DPRG (Dallas Personal Robotics Group) got me stared on this kick about ‘roughness’ mapping and area extraction from video based upon that. That among 100 other items were on my play list for this robot.
You’ve sure have been involved in a wide variety of projects. Makes me a little jealous. My career path has been much different but I wouldn’t change much. I still think a robot to deal with dandelions would be something that would sell. Like a Rumba maybe only bigger. Maybe a laser to toast the tap root.
There were a handful of related side-projects while building the robots. One of those was making a set of 4x heavy duty lift/hoist stands. Especially when wiring, as these beasties get heavier, aproaching their design weight, the stands come in invaluable with the electric hoist and the ability to swing / rotate them around or set them down on a cart to run them out to the garage, etc…
A couple construction photos…
I ended up making a couple different flavors to hold different robots with different mounting requirements…
I quite enjoy the following photo. Something about nice heavy duty parts hogged out of 1in material. If you look closely, you can see that I left a heavy chamfer at the bottom of each pocket to stress relieve the part and prevent cracks from forming over the years. That combined with the coatings will go a lnog way towards maintaining these for many many years to come.
In the image above the biggest compromise I made in the design was the use of stainless-steel screws. I had performed the original calculations based on the shear strength of grade-5 or better bolts. At the end of the project, I had stainless steel on hand, so I went ahead and used them. This substitution cuts down on the design margin / safety factor considerably.
The cable hoists are rated for ~800lbs when operated with the pulley in the configuration I’ve got it in. This is well more than enough, but as a future improvement, I ‘may’ go back and add a 2’nd double pulley configuration to both the top and bottom. The goal is not to increase the lifting capacity, rather it goal in doing that would be to drop the lifting speed by a factor or 4x.
Keeping a large amount of similarity between the 4x hoists lent itself well to mass production of some of the parts… The photo below is from “unboxing day” as I sent these parts out to a company (Aero Finnishing in Arlington Wa.) for anodizing.
The hardest part of this process was deciding where to mount these. They have a ~12in diameter base, each of which has 4x1/2in concrete anchors. Additionally the tops of all of them are connected by 3"x3"x1/4in wall tubing, so I’m not planning to move them any time soon. I have re-arranged the studio one time since I put them in and these layered in a signification number of constraints on that process.
This was one of the last big projects I did right before buying my AVIDcnc.