I need help thinking about two events happening simultaneously.
I have a heavy block on a surface with static and kinetic coefficients of friction, though they are unknown. The block is connected to a linear actuator that will pull with a constant velocity (not varying force) when powered. Between the block and the linear actuator is a load cell that will read real-time force, so the load cell is in tension. Let's assume the load cell is in perfect alignment with the actuator and the block so it is not being loaded in a way to give false readings and its sampling frequency is appropriate. The purpose of this experiment is to measure the force to overcome static friction between the block and the surface.
Ok, so I power the linear actuator and it moves from rest to its rated constant velocity. The load cell gives readings: ramps up quickly to a peak then decreases and stabilizes when the block is sliding at a constant velocity. Here's my question: I didn't think that the velocity of the linear actuator had anything to do with the peak load cell reading, but I think it does. I think I'm overcoming static friction at the instant I'm also accelerating the block from rest to the rated velocity of the linear actuator. Would these "combined" forces happening pretty much simultaneously be reflected by the higher than expected force readings on my load cell?