The Servo Shield gives your OpenMV Cam the ability to control up to 8 servos in parallel. It features the PCA9685 Servo Controller which can also do general-purpose PWM. We've got a PCA9685.py script for controlling the chip for general-purpose PWM and a Servo.py script for controlling servos using the PCA9685 general-purpose PWM script.
The Servo Shield is great for applications where you need to use your OpenMV Cam to control things in the real world. For example, it works great for turning an RC car into a self-driving car using your OpenMV Cam for vision and the servo shield to control the throttle and steering motors. Typically ESCs supply voltage out on their servo pin headers instead of requiring voltage. So, if you hook the servo shield up to your OpenMV Cam and an ESC up to your servo shield everything will be powered. Then you can hook up more servos on the other channels.