I'm working on a project that needs to control mechanical elements with very high precision. The current approach is employing an arduino UNO and an 8 bit DAC and an op amp to drive piezo elements (up to 15 V). While this works, the mechanical movement is far from smooth and causes unwanted vibrations due to stepwise movement.
I've looked at direct synthesis methods, pwm + low pass filter combinations that seem to be popular in audio context, but due to the resolution of the digital write, i think it might be hard to get a smooth waveform at low frequencies.
Does anyone have experience in generating smooth low frequency signals (1-2 Hz)? I've been thinking of cycling the DAC between different levels akin to PWM to get even higher resolution but ı'm not sure if that would be feasible or even whether it would work better than arduino's native PWM.