CN211318794U

CN211318794U - TOF human presence detection system

Info

Publication number: CN211318794U
Application number: CN201921753916.9U
Authority: CN
Inventors: 杨军黄
Original assignee: Shenzhen Hengyi Technology Co ltd
Current assignee: Shenzhen Hengyi Technology Co ltd
Priority date: 2019-10-18
Filing date: 2019-10-18
Publication date: 2020-08-21
Anticipated expiration: 2029-10-18

Abstract

The utility model relates to a human detecting system that exists of TOF in intelligence official working field. The device comprises a power supply, a TOF sensor and a main control chip. The main control chip is provided with a power supply interface, a CAN interface, a wireless transmission interface, an I/O interface and an RS232 interface, and is in communication connection with the TOF sensor through an I2C protocol. The power supply is internally provided with a DC-DC chip for supporting wide voltage input of 6V-28V. The wireless communication module is further included to realize wireless communication with the upper device. The utility model discloses it is more accurate to make the human result that exists the detection with TOF sensor with corresponding circuit connection, and the error is little.

Description

TOF human presence detection system

Technical Field

The utility model relates to an intelligence official working technical field, the human existence detecting system of concretely relates to TOF.

Background

At present, for the private fields such as conference rooms, fitting rooms, third toilets, hotels, bathrooms and the like, if people are required to be detected in the rooms, a PIR human body pyroelectric infrared sensor is usually adopted to detect whether people are in the rooms. The biggest drawbacks of PIR technology, however, are: when a person stands still, the PIR human body pyroelectric infrared sensor cannot detect whether the person is present or not, and false alarm is often generated when abnormal light is detected.

SUMMERY OF THE UTILITY MODEL

The utility model aims at overcoming the not enough and defect of prior art, provide a human existence detecting system of TOF that detects more sensitively, more accurate.

The purpose of the utility model is realized through the following technical scheme:

human detection system that exists of TOF, including power, TOF sensor and master control chip, access power between pin VDDA and the stitch VSS on the master control chip, stitch CAN _ RXD and stitch CAN _ TXD are used for accessing the CAN bus, the indirect TOF sensor of stitch I2C _ SCL and stitch I2C _ SDA, in addition, still be equipped with wireless transmission interface, IO interface and RS232 interface on the master control chip, the external RS485 interface chip of RS232 interface, RS485 interface chip converts the RS232 signal into RS485 protocol signal.

Specifically, the RS485 interface chip is used for communicating with an upper device.

Specifically, the model of the main control chip is CORTEX-M0.

Specifically, the model of the TOF sensor is VL53L 1X.

Specifically, the wide voltage power supply of 6V-28V is supported, and the power supply converts the input voltage into 3.3V low voltage through a DC-DC chip to supply power for the TOF sensor and the main control chip.

In particular, the system also comprises a wireless communication module.

Compared with the prior art, the utility model following advantage and beneficial effect are included:

(1) the utility model discloses a TOF sensor replaces the human pyroelectric infrared sensor of PIR, is aided with main control chip and external port, has reduced the human error that exists the detection. Power adaptation DC-DC chip to the wide voltage input of adaptation 6V ~ 28V makes the utility model discloses stronger adaptability has.

(2) The utility model discloses main control chip passes through the RS485 interface and converts main control chip RS232 signal into RS485 signal and external communication, and the user defines communication protocol by oneself conveniently in the use.

Drawings

Fig. 1 is a working principle diagram of the present invention.

Fig. 2 is a schematic circuit diagram of the main control chip.

FIG. 3 is a circuit schematic of a TOF sensor.

Fig. 4 is a circuit schematic diagram of an RS485 interface.

Fig. 5 is a circuit schematic of the power interface.

Detailed Description

The present invention will be described in further detail with reference to the following examples and drawings, but the present invention is not limited thereto.

In the description of the present invention, it is to be noted that the terms "provided, connected, etc. are to be interpreted broadly unless explicitly defined and limited otherwise. Furthermore, the utility model discloses a parts such as main control chip, TOF sensor are the parts that general standard component or field technician know, and its structure and principle all are this technical staff and all can learn through the technical manual or learn through conventional experimental method.

As shown in fig. 1 to 5, the specific implementation process of the present invention is as follows:

the TOF human presence detection system comprises a power supply, a TOF sensor and a main control chip. The main control chip is in communication connection with an external device through pins, wherein the external device comprises a TOF sensor, a wireless module, an RS485 interface, a CAN interface and an I/O interface.

The main control chip uses ST, the type of the high-performance CPU is CORTEX-M0, the main frequency reaches 48MHZ, the main control chip is connected with the TOF sensor through an I2C interface, and the main control chip is connected with an RS485 interface chip through an RS232 interface to communicate with the upper equipment.

A power supply is connected between a pin VDDA and a pin VSS, and the TOF human body existence detection equipment in the embodiment is suitable for wide voltage input of 6V-28V. The power interface is used for being connected to a power supply to supply power for the TOF sensor and the main control chip, comprises a DC-DC chip, and can convert input voltage into 3.3V low voltage to charge the main control chip and the TOF sensor. The output power Vout is 0.807 ═ 1+ 40.2/13. The circuit principle of the DC-DC chip is shown in fig. 5, pin 1 is connected to an input power source, resistors C3201 and C3202 are connected in parallel, one end is connected to the input power source, the other end is grounded, pin 1 and pin 5 are connected through resistor R3201, and pin 3 is grounded; pin 4 is connected in series with resistor R3205 and capacitor C3203, and is connected with the power output end after being connected with pin 2 in a junction way; the pin 6 is connected in series with the resistors R3202 and R3203 and connected to the power output terminal, wherein the resistor R3203 is connected in parallel with the capacitor C3206, and one end of the capacitor C3206 is grounded.

The pin CAN _ RXD and the pin CAN _ TXD are used for being connected into a CAN bus, and a CAN bus protocol effectively supports a serial communication network controlled in real time so as to realize real-time updating of a detection result.

A TOF sensor is connected between a pin I2C _ SCL and a pin I2C _ SDA, the TOF technology is that the sensor emits modulated near infrared light and reflects the near infrared light after meeting an object, the distance of a shot scene is converted by the sensor through calculating the time difference or phase difference of light emission and reflection so as to generate depth information, and in addition, the three-dimensional outline of the object can be presented in a mode that different colors represent topographic maps of different distances by combining with traditional camera shooting. Therefore, the TOF sensor can overcome the problem that the traditional PIR human body pyroelectric infrared sensor has in the detection process, and immediately and accurately reports the detection result of whether a person exists to the upper equipment, so that the upper equipment can analyze the detection result and send an instruction to the next-stage equipment.

Specifically, the model of the TOF sensor is VL53L 1X.

In addition, still be equipped with wireless transmission interface, IO interface and RS232 interface on the master control chip, the external RS485 interface chip of RS232 interface, RS485 interface chip is RS485 protocol signal with RS232 signal conversion, through RS485 interface chip and upper equipment communication. The schematic diagram of the connection is shown in figure 4.

The RS232 on the main control chip is in a full-duplex working mode, the voltage of a signal is obtained by referring to a ground wire, and data can be transmitted and received simultaneously. However, RS232 has only a single station function, i.e., one-to-one communication. In the RS232 wiring diagram, TXD and RXD are connected to the CAN bus through a resistor R3207 and a resistor R3208, respectively, to achieve transmission and reception of signals, and the RS485 bus protocol uses positive and negative signal lines as transmission lines. The voltage difference between the two lines is +2V to 6V and represents logic 1: the voltage difference between the two wires is-2V to 6V, indicating a logic "0". RS485 is a half-duplex working mode, signals of the RS485 are obtained by subtracting the signal levels of a positive line and a negative line, the RS485 is in a differential input mode, the common-mode interference resistance is strong, and the noise interference resistance is good; in practical application, the transmission distance can reach 1200 meters. RS485 has multi-station capability, i.e. one-to-many master-slave communication.

Specifically, the numerical control chip is further provided with an I/O interface for connecting external equipment, so that communication interconnection among the equipment is realized.

Specifically, the system further comprises a wireless communication module for wireless communication.

The utility model discloses a concrete implementation way does:

the TOF sensor is connected with the main control chip and integrated together, and the suspended ceiling is installed in places such as a dressing room. The main control chip passes through the RS485 interface, the CAN interface, wireless module, the communication interconnection between I/O interface realization and the external device, the main control chip is each second time through the infrared light test that TOF sensor received and calculate the distance to ground many times, thereby judge whether the bottom surface is someone, after detecting that the distance has changed, compare with the "someone" signal threshold value that sets up in the main control chip, reach whether someone, judge "someone" when the testing result, send "someone" signal through the external interface through the main control chip, set up equipment that has indicateing such as display screen or pilot lamp outside the space usually, thereby show the testing result directly perceived.

The above-mentioned embodiments only express the embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

A TOF human presence detection system, characterized in that: including power, TOF sensor and main control chip, access power between pin VDDA and stitch VSS on the main control chip, stitch CAN _ RXD and stitch CAN _ TXD are used for accessing the CAN bus, stitch I2C _ SCL and stitch I2C _ SDA's indirect TOF sensor, in addition, still be equipped with wireless transmission interface, IO interface and RS232 interface on the main control chip, the external RS485 interface chip of RS232 interface, RS485 interface chip is RS232 signal conversion to RS485 protocol signal.
2. The TOF human presence detection system according to claim 1, wherein: and the RS485 interface chip is used for communicating with an upper device.
3. The TOF human presence detection system according to claim 1, wherein: the model of the main control chip is CORTEX-M0.
4. The TOF human presence detection system according to claim 1, wherein: the model of the TOF sensor is VL53L 1X.
5. The TOF human presence detection system according to claim 1, wherein: the power supply supports 6-28V wide voltage power supply, and the power supply converts input voltage into 3.3V low voltage through a DC-DC chip to supply power for the TOF sensor and the main control chip.
6. The TOF human presence detection system according to claim 1, wherein: also included is a wireless communication module.