The vast majority of automated machine tools, including 3D printers, laser cutters, and CNC mills, have a Cartesian layout. That means they move linearly in the X, Y, and Z axes. It’s a popular layout because it’s predictable, relatively inexpensive, and offers good rigidity. But, that doesn’t mean the Cartesian layout is the best in every situation. Delta robots can accelerate quickly and operate at high speeds, which makes them ideal for applications like pick-and-place. They’re more complicated to build, but YouTuber Anthony of Proto G Engineering is making great progress on his.
Delta robots can be constructed in a couple of ways, but they all utilize a set of three linkages (or linkage pairs) that connect motors or actuators to a central end effector mount. By adjusting the positions at one end of those linkages — usually their height — the end effector can be moved anywhere within a roughly cylindrical work envelope. In this case, the linkages are rigid and connected directly between arms on massive stepper motors and the end effector mount, which means it can move very quickly and without much backlash.
To control it, Anthony designed a custom PCB to breakout an ESP32 module. That has support for magnetic encoders, step and direction signals for the steppers, vacuum pump and solenoid for the pick-and-place end effector, and even a camera for computer vision. The goal is for the robot to eventually be able to identify, grab, and then place individual objects. It’s not quite there yet, but Anthony has already made a ton of progress, and we’re really excited to see the finished robot.