Answer: ABC
Analysis: It is correct that a bridge consisting of resistive strain gauges can constitute a sensor that measures weight.
A resistance strain gauge is a sensor element that can convert the change of physical quantity (such as stress, strain, acceleration, etc.) into a change in resistance, and convert the change of resistance into a change in voltage or current through a bridge circuit, thereby measuring the change of physical quantity.
When measuring weight, a resistive strain gauge can be attached to the object to be measured, and the change in gravity can be converted into a change in voltage or current through a bridge circuit, thereby measuring the change in weight. Therefore, it is correct that a bridge consisting of resistive strain gauges can constitute a sensor that measures weight.
The weight of bulk material is detected correctly. A laser rangefinder is an instrument that uses a laser to measure distance, which can measure the distance between objects and then calculate the weight of the object. In bulk material weight detection, the laser rangefinder can be installed in a fixed position to calculate the weight of the cargo by measuring the distance between the cargo and the silo, combined with the size of the silo and the density of the cargo. Therefore, it is correct that the laser rangefinder can detect the weight of bulk materials.
The electronic gear mode of motion control is a follow-up system in which the active shaft maintains a flexible transmission ratio to the driven shaft. And rightly so.