Pseudonymous YouTuber “The 5439 Workshop,” hereafter merely “5439,” is engaged on a mission to construct a bipedal robotic — starting with designing a novel kind of 3D-printable actuator, pushed by an Espressif ESP32 microcontroller.
“I’ve wished to construct a bipedal robotic for a very long time — and now it is lastly taking place! I am taking the Disney strolling robotic as inspiration, however I’ll make it my very own design,” 5439 explains. “The factor I really like about it’s that it is filled with character and animated not just for effectivity however to additionally to convey feelings in the way in which it strikes. I am designing customized 3D-printed robotic actuators — the core of the robotic. As an alternative of utilizing the standard setup in relation to a rope/cable drivetrain, I’ve developed a brand new actuator design (not less than I have never seen this actual strategy earlier than!). It isn’t the best approach, nevertheless it’s the trail I take pleasure in.”
The issue 5439 is attempting to unravel — aside from an itch to do one thing new — is straightforward: the tendency for 3D-printed actuators to wear down too quickly. The standard repair for that is to make use of a rope-drive system as a substitute of conventional gears, which is best suited to 3D printing however leads to a bulkier actuator than desired.
“Here is the concept,” 5439 says of the mission’s novel strategy. “We’ll take the rope drive and bend it over two pulleys. Then we’ll take the motive force and open it up so it matches across the drive prepare. And at last, we place the encoder within the stator.”
Preliminary testing revealed an higher torque restrict due to splitting across the pulley wheels. (📷: The 5439 Workshop)
Preliminary testing of the design confirmed a difficulty with flexing, which restricted the torque to round 6.5 newton-meters (Nm). The addition of metallic sheets elevated rigidity, however the torque nonetheless did not scale: 1A delivered 5Nm, however 5A solely raised that to 9Nm. “I attempted a bunch of stuff,” 5439 says, “till I discovered this: the pulley wheels are splitting at increased forces, creating a variety of friction and resistance. This explains our outcomes.”
The complete video is out there embedded above and on 5439’s YouTube channel; design information for the actuator haven’t but been publicly launched.
