Stm32f1 and stm32cubeide programming example - rotary encoder drive

Rotary encoder drive

1、 Introduction to rotary encoder

Rotary encoder , Also known as shaft encoder , It is a kind of electromechanical equipment , The angular position or movement of the shaft or shaft can be converted into analog or digital output signals . There are two main types of rotary encoders ： Absolute and incremental . The output of the absolute encoder indicates the current axis position , Make it an angle sensor . The output of the incremental encoder provides information about shaft motion , This information is usually processed into locations elsewhere 、 Speed, distance and other information .

Rotary encoders are widely used in applications that require monitoring or control of mechanical systems, or both , Including industrial control 、 robot 、 Photographic lens 、 Computer input device （ Such as optical mechanical mouse and trackball ）、 Controlled stress rheometer and rotating radar platform .

The encoder technology types are as follows ：

• conductive ： Etch in PCB A series of circumferential copper traces on the are used to encode information . The contact brush senses the conductive area . In addition to the user input in the digital multimeter , This form of encoder is now rare .
• optics ： This uses light that strikes the photodiode through a slit in a metal or glass disk . Reflective versions also exist . This is one of the most common technologies . Optical encoder is very sensitive to dust .
• Coaxial magnetic ： This technique usually uses special magnetization attached to the motor shaft 2 Neodymium magnet . Because it can be fixed at the end of the shaft , Therefore, it can be used with a motor with only one shaft extending out of the motor body . Accuracy can vary from a few degrees to less 1 degree . The resolution can be as low as 1 Degrees or as high as 0.09 degree （4000 CPR, Count per revolution ）. Poorly designed internal interpolation will cause output jitter , But this can be overcome by averaging the internal samples .
• Off axis magnetism