Motion control - H bridges and movement

In my last post I was talking about getting the feedback mechanism from a printhead carriage up and working. This enabled me to track how much relative movement of the carriage had occurred, but didn't enable me to make the thing move! That comes in this part. In order to get motion happening, I need something that can handle the voltages/currents the motor needs - a job for an H bridge!

Arduino, Motion Control and Encoders

I took a failed Canon Pixma all-in-one inkjet apart in order to see how it was engineered. I also extracted some of the mechanics so I could learn a bit more about motion control in the real world. This post is about that exploration. I was primarily interested in the printhead carriage, as it has a feedback loop to provide information back about the speed of the carriage and which direction it is travelling in.

The printhead carriage itself is little more than some mechanics in the form of a sliding assembly that holds the printhead, a DC motor driving a belt, an optical strip and a pair of optical sensors and an LED.