LabVIEW Grade Status

Project concepts must fulfill three primary criteria:

1) The project must measure something in the real world. The thing measured should not consist of only Boolean quantities (e.g., does some photo-sensor detect light?). So, in the ideal case, a project must (repeatedly) make at least one measurement that is best represented by a floating point number. So, the position of a ball, the brightness of a light, the temperature of a fluid, or the frequency of a sound are all reasonable quantities. I would also entertain proposals in which the thing(s) being measured consist of a dozen or more separate Booleans.

2) The project must control something in the real world. The thing controlled should not consist of only Boolean quantities (e.g., turning on a light or turning on a motor). In the ideal case, a project must (repeatedly) control at least one output that is best represented by a floating point number. So, the angular position of a motor, or the frequency provided to an AC circuit, or the frequency provided to an audio speaker are reasonable quantities.

3) The project must include negative feedback. Broadly speaking, negative feedback means that the system as a whole is seeking to achieve some kind of balance. So, if something is moved too far to the right compared to its desired position, it seeks to move it back to the left. Or, if a light is too bright, the system moves the sensor away from the light. The "negative" refers to these directions... if it's too far to the right, it goes left. If it's too bright, it tries to make it dark. Classically, when you move an object away to reduce brightness (for example), you'll almost certainly move it too far away, so you'll then need to move it closer again. A reasonable way to see whether you have negative feedback is to write a summary sentence for the project that is centered around the word "until": "the project will adjust the AC voltage frequency until resonance is achieved."

Generally, when negative feedback is present, then adjusting the output also adjusts the input. So:

NOT negative feedback: I will change the light intensity until the brightness is correct.

IS negative feedback: I will move the light sensor until the brightness is correct.