Robots have that exciting convergence of Electronics and Mechanics creating a platform full of sensory data for analysis - all with automation and artificial intelligence.
I am following my passion for creating roving robots that can explore the universe - one step at a time. I am exploring the design and build process, both learning and sharing along the way.
Here is the latest print and video of the Centipede Project.
moving from OpenSCAD to print went fairly smoothly. As you can see, I have enclosed the main rotating mechanism that moves the chopstick legs. In this design in OpenSCAD, I have rotated everything along the Z axis, to make it easier to keep centered. The covering socket cap and ball all align, as well as the cam. You can also see holes along the structure, so that small screws can be used to assemble the leg segment. I am reusing screws from recycled printers that are used to bind plastic parts together.
At the 'base' of the leg, I have created a hexagon. This seems to me to be 'self-bio-inspired'. I have not used hexagons in previous designs, so it is novel to me. More importantly, it fits the nature of the leg, as there is no specific 'down' or 'up. One the walls of the cam base, I have added two small holes for M3 bolts. This allows me to connect two or more legs in sequence... thus forming the multiple legs of the Centipede.
At this time there are only two leg segments connected. The M3 bolts are not visible, as they are inside the cam housing. Note: I had a near-fail as I forgot to leave clearance between the cam housing wall and the bearing mount. There are many issues to design out when doing project like this. This is why physically making the prototypes is very important to realize assembly issues.
New Gears to connect to Drive
At the base of the Cam Housing are two gears attached to the cam itself. The cam shaft runs through a bearing and then is connected to the gears. The gears are "kegelrad" from the OpenSCAD library "Getriebe Bilbiothek für OpenSCAD". The kegelrad could give me an ability to mount the drive gears at an angle different from the cam housing. We shall see! ;)
I have published a video of the initial design and 3D Printed "drafts" of the Centipede leg mechanism. You can find the video below on my YouTube channel.
From a design perspective, the drafts have served their purpose. It is now a good time to take what we have learned and start a new draft. I like the concept of making each leg of the Centipede to be a "module" that can be replicated and connected together. I am also realizing that I don't care much for the 'rectangular' frame that was in the drafts. The legs may need to be moved around. Honestly, the rectangles do not seem to match the aesthetic of an bio-inspired robot. Here is my new concept that I am working on ...
I have just posted a YouTube Video of the assembly of the Wild Weasel track. You can find it here:
Wild Weasel a completely 3D printed Tracked Robot. I wanted to build a tracked robot, due to their stability, and at the same time use some motors that I had recovered from recycled printers. The project went very smoothly, a lot of CAD work was need to design the treads, chassis, and gears used. The robot uses a Raspberry Pi and an L298N motor driver. This was my first time to use a Tallent Cell power bank, which provides 12V and 5V power - great for RPI and the motors.