For our second experiment completed in class, we used the Lego Mindstorm motor to lift weights with a pulley to detect certain measurements. Some of the measurements we were able to determine were the acceleration, battery discharge, the mass, the power (energy=time), and the time of acceleration. We used the VI program again to pick different Power Levels to measure the acceleration of the weights when we would run the pulley. We were able to read the battery level of the connected NXT and measure the outputs of the power level in millivolts. In addition to that, we used excel to calculate the results. The following chart displays the Battery Discharge we got in result of putting the Power Levell at 60%. We set the motor at different speeds (RPM), such as at 63.36245 (with a battery discharge of 55 and a mass of 0.245kg), 66.19594 (with a battery charge of 42 and a mass of 0.19kg), and 69.79716 (with a battery discharge of 14 and a mass of 0.15kg).
The chart below displays that when we set the Power Level to 40%, we got an acceleration of 11.32843 RPM/s and when we set the Power Level to 80%, we got an acceleration of 60.38247 RPM/s.
This next chart shows:
– when we made the Power Level 60%, it resulted in a Power (energy/time) of 0.021131
– when we made the Power Level 40%, it resulted in a Power (energy/time) of 0.011942
– when we made the Power Level 80% it resulted in a Power (energy/time) of 0.027614
And last but not least, this chart below displays the results in acceleration from different measurements of the mass in kilograms. The results we detected was an acceleration of 24.06474 RPM/s with a mass of 0.245kg, an acceleration of 29.21268 RPM/s with a mass of 0.19 kg, and an acceleration of 33.44377 RPM/s with a mass of 0.15 kg.
Just by looking at these graphs, we can determine that the less mass, the bigger the acceleration. This makes sense because Newton’s 2nd law says force=mass * acceleration. The law says that if an equal force is applied to a larger mass. it will accelerate proportionally more slowly. This also means that if you push on two objects with identical force, the object with the smaller mass will have a greater acceleration. Mass is directly related to acceleration, meaning that if one goes up, then the other has to go down. These graphs show the acceleration for a function of mass as a constant parallel. With a larger mass, acceleration should go down as a function of force for a fixed mass.