StepForge 28BYJ-48 Stepper Motor Controller
About this project
StepForge drives a 28BYJ-48 unipolar stepper motor through a ULN2003 Darlington driver using a manually implemented half-step sequence — no AccelStepper library, no abstraction. The 8-row step sequence table directly encodes which of the four motor coils to energise at each position, advancing the motor one magnetic pole at a time through 4096 half-steps per revolution. All motion runs non-blocking via micros()-based timing — the LCD, Serial Monitor, and STOP button remain fully responsive even while the motor is moving. A serial command interface accepts FWD, BACK, GOTO, HOME, ZERO, RPM, SWEEP, POS, STOP, and INFO commands typed directly from the Arduino IDE Serial Monitor. The LCD shows current absolute position, target position, and RPM setting in real time. The project covers six concepts fundamental to embedded motor control: half-step vs full-step excitation, the ULN2003 Darlington transistor array and back-EMF flyback diodes, micros()-based velocity control, open-loop position tracking with step counter, serial command tokenisation with strtok(), and coil deenergisation to prevent motor heating at rest. Build time: 2.5 hours.
What you get
- Complete, commented source code
- Full components list with quantities
- Pin-by-pin wiring guide and connection table
- Step-by-step upload and testing guide
- Project report (.docx, IEEE style)
- Presentation slides (.pptx)