Yesterday, I completed my fifth motor controller board, containing two of Steve Bolt’s Four Transistor H-Bridges The first was an old-fashioned SPST/DPDT relay controller, the second was based on a pair of BA6219B chips I salvaged from an old VCR, the third was a UCN5804B stepper driver, and the fourth was a set of pure transistor (TIP41B) H-bridges. Since I can now control up to 8 DC motors, and since I’m pretty sure I can throw future motor controllers together whenever I need them, I think I’ll move my attention to sensors.
I think I’ll start with such low-tech sensors as bump switches and CdS cells. I like the idea of giving my robot feelers, but I haven’t seen a design for them that I’ve really liked. As for CdS cells, I think I’ll just go with a four-cell design I found in Robot Building for Beginners