We had good success with our 16-legged walking creature Aluminalis, so we decided to use what we learned and build a new walking creature. We plan for this to be a much smaller, faster, and more agile little beastie. We call her Alumini (Ah-lu-min-ee). Instead of 22″ wide, she’ll be just 10″ wide. Instead of using bulky rectangular segments, we’ve designed much finer segments, like bones in a spine, with built-in pockets for ball bearings to hold the all-important crankshafts. We’ve also designed a custom motor-and-gear mount for each end that holds everything together. Alumini will have twelve legs instead of sixteen. And instead of having a large visible thorax (body), all the electronics will be integrated within and beneath the legs of the robot, so she’ll appear to be nothing but legs. Here are some pictures of our work-in-progress. The crankshaft and legs are not shown. We’re just working on the skeleton and overall structure at this point.
MOTOR AND GEARS MOUNTED ON CUSTOM END PIECE
BONE-LIKE SPINE SEGMENTS MACHINED ON CNC
SPINE SEGMENT WITH BALL BEARINGS (TO HOLD CRANKSHAFT) INSTALLED IN SPINE
CLOSE-UP OF MOTOR-AND-GEAR MOUNT
CNC COVERED IN CHIPS AFTER MACHINING THE PARTS FROM A 12″ x 12″ SHEET OF 1/4″ THICK 6061 ALUMINUM
CNC-MACHINED CRANKSHAFT ARMS ALONG WITH BALL BEARINGS AND SHAFTS
I am a Software Engineer (senior), but as far as machining goes, Camille and Genevieve are my idol and source of inspiration.
what is involved in setting up the cnc for a new peice? how do you design it?
Jake: We design the part in the SolidWorks CAD package. We then use the HSMWorks Express CAM-package to plan out the CNC cutting operations (indicating what tool to use, which contours to cut, how much material to take off in each pass, the speed and feed rate, and so on). The CAM package automatically produces the the g-code file, which is the detailed instructions to the CNC. We then boot up the CNC and load the g-code file. To setup the CNC, we clamp down the material, zero the tool (https://beatty-robotics.com/zeroing-a-cnc/), and then tell the CNC to go. Please note that we machined each of these parts individually, one at a time. We didn’t machine them all at once (although we theoretically could the next time). We’ve done our best to streamline the process, so it takes about 20 minutes to clamp down the material and get set up. Then it takes the CNC about 7 minutes to cut the motor mount, 5 minutes to cut one of the segments, and 2.5 minutes to cut one of the crankshaft arms. It’s .250″ thick material, which is quite thick (for us), so we do it at 0.040″ or 0.025″ per pass with a .125″ flat end mill.
Beautiful machine and beautiful machinist. Love the name Alumini.
Thanks, John. Good to hear from your neck of the woods. 🙂
Boy, you are doing wonders with that CNC machine. Fabulous work.