Dali Md16u Human Body Temperature Measurement Module User Manual

User Manual
MD16U Human Body Temperature
Measurement Module

Rev. 1.0
Zhejiang DALI Technology Co., Ltd.
MD16U thermal imaging module user manual

Product Introduction

The MD16U human body temperature measurement thermal imaging module is developed by DALI manufactured uncooled microbolometer detectors. MD16U outputs data with a resolution of 120×322 in UVC mode. The pseudo-color image and the temperature image are spliced up and down and output at the same time. The upper 120×160 is the pseudo-color image, the lower 120×160 is the temperature data, and the last 2 lines of information output other information.
The module supplies power through the USB interface, communicates control and data output in UVC mode, and is easy to integrate with other application systems.
MD16U module can be connected to a computer for independent application and is also suitable for integration with other human body temperature measurement and screening equipment: temperature measurement flat panel, temperature measurement gate, temperature measurement security gate, temperature measurement attendance machine, temperature measurement access control intercom and other equipment

Picture .1：MD16T Module appearance

MD16U Features and Advantages：

• Integrated mini black body, high-temperature measurement accuracy, stable performance, and small influence of working environment temperature.
• Full-frame human body temperature measurement: Each frame of the image provides 160×120 temperature point data, suitable for various applications.
• UVC output to realize drive-free development
• Small size, convenient installation, universal single USB cable input, and output
• Flexible application: users can perform personalized algorithm processing such as back-end image stretching and pseudo-color rendering.

Precautions for module use:：

• Use in strict accordance with the specified use conditions of the product, and the module needs to be used in an indoor no wind scene.
• When the system is used in integration, it is necessary to strengthen the heat dissipation and ensure uniform and stable temperature around the module and be isolated from other cold/heat sources to avoid severe fluctuations in ambient temperature.
• Take care to protect the surface of the lens to avoid scratches and oil stains from hard objects.
• The module should not look directly at high-temperature targets such as the sun to prevent high-temperature burns to the detector.

Technical Specifications

The detailed technical parameters of MD16U are described below：

Table 1：Technical Parameters

Mechanical Parameters

The dimensions of the module are shown in Picture 2(unit： mm)

Picture 2：Module dimension

Electrical Parameters

The module output interface is a USB Type-A male data cable, which works in USB2.0 mode.
Power requirements input range 4.4V ~ 5.5V, currently greater than 500mA, more than 1A is recommended

Software protocol

The module is a UVC slave device with a VC interface and a VS interface inside.
The VC interface is used for module control, and the VS interface is used for image and temperature data output.
Use the “contrast” adjustment command in the VC interface to issue control commands, upload module response information, and control the basic composition and format of transmission data packets as shown in Table 3.

Table 3：Packet format

CRC1 check: CCITT-16 checksum is used, CRC-CCITT （ 0xFFFF ）， that is CRC-16/CCITT-FALSE
a) The check operation is performed on the four parts of “No. 1”-“No. 6”.
b) The check is formed at the backend and is checked at the module side. If the check fails, it needs to be retransmitted.
CRC2 check: CCITT-16 checksum is used, CRC-CCITT （ 0xFFFF ）， that is CRC-16/CCITT-FALSE。
a) The check operation is performed on the six parts of “No. 1” – “No. 9”.
b) The check is formed at the backend and is checked at the module side. If the check fails, it needs to be retransmitted.
The table used for CRC1 and CRC2 checks is shown in Appendix 1

Table 4：Command

Note 1: The command packet is transmitted by using the “contrast” adjustment command of UVC. Only 2 bytes must be transmitted at a time. Therefore, when the length of the command packet (number of bytes) is not an even number, it needs to be filled with zeros at the end. Special attention should be paid to the high and low bits of the sending command. For example, the length (number of bytes) of the first 6e 00 00 04 00 01 1d 4a 00 00 00 is odd, and 0 should be added to 6e 00 00 04 00 01 1d 4a 00 00 00  00 , the module needs to receive the information in this order. If it is sent from a computer, the computer transmits the problem of size end and the content that needs to be sent on the computer is as follows
0x6e 0x00;
0x00 0x04;
0x00 0x01;
0x1d 0x4a;
0x00 0x00;
0x00 0x00;

Note 2; Firmware Upgrade Instructions
The firmware data is sent to upgrade through UVC instruction, and 0x84 is used.
The process is:
A. Send the 0x84 downlink command for the first time, notify the module to enter the firmware upgrade state, and inform the firmware of the number of data packets (Byte),  the module responds to the 0x84 command and returns 0x00, indicating that it is ready;
B. Send the 0x84 downlink command for the second time to notify the module of the total length, check the code, modification time, and version number of the firmware file to be upgraded. The module responds with 0x01, indicating that the packet number of the first data packet is requested, starting from 1;
C. Next, divide the firmware size into multiple packages by 12796Byte each time, each package is accompanied by the package number and length of the current package, and send all firmware data in turn through the 0x84 command. Note that CRC2 needs to be calculated correctly, and the modulo Each time the group receives a 0x84 firmware data packet, it will return a 0x84 response command to notify the upper computer that the reception is completed and request the packet number of the next data packet. If there is no 0x84 response, the current packet needs to be resent.
The last data packet may be less than 12800Byte in length, and it is sent according to the actual data length.

UVC Output

The module is a UVC slave device, and the VS interface is used for data transmission. When outputting data, the format is YUYV, and the size of each pixel is 2Byte.
The default state of the module is to output a pseudo-color image and temperature image at the same time, and the output resolution is 120×322. Lines 1 to 160 are pseudo-color images, lines 161 to 320 are temperature data, and the last two lines are status information.
The module can also be switched to output only pseudo-color image data, or only output temperature data, the output resolution is 120×162, the first row to the 160th row is pseudo-color image data or temperature data, and the last two rows are status information.
When acquiring data, the data is first read in the YUYV method, the pseudo-color image data is directly converted to RGB output, and the temperature data is converted to grayscale. The conversion relationship between the temperature measurement value Tc (°C) of the detection target and the grayscale value Vc (grayscale) of the temperature data is Tc= Vc/10–273;

In the output data, the last two lines are used to display the status information, and the information of each part is shown in Table 5. For the information of the two lines of status bits, the starting position is at the position of 0 points of the last two lines, after outputting the data of the previous array, the next 12Byte is the detector type. That is, Table 5 is output in order from the 0-point position of the last two lines.

Table 5: Information Format

Note 1: TOUT gray value, shutter gray value, center point information, highest point information, and lowest point information are all in little-endian mode.
Note 2: The conversion relationship between the internal temperature of the detector Ts (°C) and the module TOUT gray value Vs (gray) is:
Ts = 190.64 – 0.02164 × Vs
(The following page is Appendix 1)

Appendix 1：

CRC checklist

The initial value of CRC is 0xFFFF.
Note: CRC does not directly check the table in Appendix 1, but is calculated according to the algorithm. The table in Appendix 1 is the table called during the calculation process. This table is used in the CRC algorithm source code.
The CRC check algorithm of the module is CRC-CCITT (0xFFFF), namely CRC-16/CCITT-FALS.