Had power/speed problems with our linear actuators coupled to an MD01B driver. Measured 8.5V as the drivers output, it took a bit but we realized the PWM out function is not based on 0-100% but 0-255 counts.
Just thought I’d pass along the info for anyonle else scratching thier head like we were for a day.
Thanks for posting. However, it sounds like you are really just talking about a specific behavior of the Arduino rather than something related to a linear actuator or motor driver. In general, it’s a good idea to always check the command reference for the API your are using rather than making assumptions about how functions will behave: