Control method of hand sweeping inductive switch

Abstract

The invention discloses a control method of a hand-sweeping inductive switch. The control method comprises the following steps: presetting a trigger threshold in direct proportion to light intensity; when the difference values between the maximum values and the minimum values of two adjacent periods are equal, continuously recording a plurality of groups and recording as reference values in the current environment; detecting the difference value between the maximum value and the minimum value of the waveform in the current environment in real time, calculating whether the difference value is greater than or equal to the sum of the reference value in the current environment and the trigger threshold value in the current environment, if so, continuously recording a plurality of groups of data and having a trend of rising and then falling, and judging that the inductive switch is swept by hands; if the difference value is smaller than the sum of the reference value in the current environment and the trigger threshold value in the current environment, it is judged that no hand scans the inductive switch; the situation that the hand scanning module does not react or is triggered by mistake when the solar environment is bright can be solved, the situation that interference is caused by a close object below the module is solved, and the solar hand scanning module can adapt to various occasions.

Description

technical field [0001] The invention relates to the field of hand-scanning inductive switches, in particular to a control method of the hand-scanning inductive switches. Background technique [0002] The hand-scanning sensor switch uses an infrared transmitting tube to emit infrared light signals, and then receives infrared light signals through an infrared receiving tube. By judging the difference between the maximum value and the minimum value (referred to as the difference) on the infrared receiving tube, it is judged whether there is a hand Sweep; but there is a great error in this judgment method, refer to Figure 1 , Figure 1 It is a waveform in an environment without sunlight. According to the above judgment method, the difference is generally set to be relatively small, about a few hundred mV, to increase the hand sweep distance. When a hand sweeps, the maximum value - the minimum value > difference, there is output; but when the sun is brighter, refer to Figure I...

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Problems solved by technology

[0002] The hand sweep sensor switch uses the infrared emitting tube to emit infrared light signals, and then receives the infrared light signals through the infrared receiving tube. By judging the difference between the maximum value and the minimum value (referred to as the difference) on the infrared receiving tube, it is judged whether there is a hand. sweep; but there is a huge error in this judgment method, refer to Figure 1 , Figure 1 It is the waveform in an environment without sunlight. According to the above judgment method, the difference is generally set relatively small, about a few hundred mV, to increase the distance of the hand sweep. When there is a hand sweep, the maximum value - the minimum value> difference, then there is output; but when there is a place where the sun is brighter, refer to Figure II , Figure II It is a waveform diagram in a relatively bright environment with the sun. The maximum value of the waveform received by the infrared receiving tube is not a fixed 5V, and it will change with the brightness of the sun. The minimum value is not a fixed value, and it will scan the module with the hand It changes with the height, and the difference is not a fixed value. It will change with the brightness of the sun and the height of the hand-swept module. The three most important parameters will change. Therefore, there is a huge error in the above-mentioned judgment method. A kind of control method of hand sweeping induction switch solves the above problems

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