This was a group project for a class I took in college called "Making It." The assignment was to make something, so we chose to make a voice-controlled robotic arm called Alf Cobot. There were four of us working on this: two worked on the mechanical design and construction of the arm, I built the embedded control electronics, and another built an iOS app that took voice commands and sent control signals to the electronics stack over BLE. It was a fun project and I got to learn about stepper driver circuits and the BLE protocol.
Today (2021) the electronics seem pretty basic to me, but back then (2018) it was a decent challenge for me to design and build this system. The architecture consists of an Arduino Mega connected to a BLE UART board (the input) and 5 DRV8825 stepper driver boards (the output) which drive the 5 stepper motors on the robotic arm. If this were today, I could easily package all this on a single board, but this was then, so I was still wiring off-the-shelf boards together rather than making my own.
Here's two pics of ALF Cobot before it was all wired up:
Today (2021) the electronics seem pretty basic to me, but back then (2018) it was a decent challenge for me to design and build this system. The architecture consists of an Arduino Mega connected to a BLE UART board (the input) and 5 DRV8825 stepper driver boards (the output) which drive the 5 stepper motors on the robotic arm. If this were today, I could easily package all this on a single board, but this was then, so I was still wiring off-the-shelf boards together rather than making my own.
Here's two pics of ALF Cobot before it was all wired up:
