16 Channel PWM board for eVOLVER Framework

One of the customizable control boards, the PWM board is designed to plug into the Motherboard and enable an Arduino to easily and quickly control many actuators (e.g. motors, LED, heaters) in parallel. For example, 16 individual LEDs can be connected to the PWM board and each of the LEDs can be set to a different brightness and updated to a different value in fractions of a second. The board has two main functions: (1) amplifying the 3.3V signal from the Arduino to a higher output voltage (5V to 24V), depending on the voltage source, and (2) expanding the Arduino pulse width modulation (PWM) capabilities from 3 to 16 channels. PWM is essential since it allows digital signals to have a more analog-like output. Analog-like outputs enable finer control of experimental parameters. For example, the temperature control of the system would be noisier if the input was toggling between the heaters fully on and off. With PWM, the user can instead use a simple PID controller to feedback from temperature measurements to optimize for a specific, highly controllable heat output. The PWM board can be daisy chained such that a single Arduino can in principle control hundreds of channels.