[Joint Laboratory] STM32 Line-Following Car | Taiyuan University of Technology

PDF_【Joint Laboratory】STM32 Line-Following Car_Taiyuan University of Technology.zip

Altium_【Joint Laboratory】STM32 Line-Following Car_ Taiyuan Institute of Technology.zip

PADS_【Joint Laboratory】STM32 Line-Following Car_ Taiyuan Institute of Technology.zip

BOM_【Joint Laboratory】STM32 Line-Following Car_Taiyuan University of Technology.xlsx

96839

Weld inspection device

The pipeline weld quality inspection device can identify weld problems at low cost, and determine the location of the problematic weld based on the length of the traction rope.

This circuit is designed to solve the problem of inspecting the quality of pipe welds. In use, it consists of a high-sensitivity light probe receiving matrix composed of multiple large-sized photoresistors. It is inspected in the pipe with a traction rope. When a weld with light leakage is encountered, the LED light on the main unit outside will light up as an alarm.

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PDF_Weld Inspection Device.zip

Altium_weld inspection device.zip

PADS_Weld Inspection Device.zip

96840

Heart rate and blood oxygen monitoring

Wearable device for real-time monitoring of blood oxygen and heart rate.

With a heart rate and blood oxygenation detection module as its core, the data reception, calculation, and transmission are controlled by an STM32F103C8T6 microcontroller. A dedicated sensor acquires heart rate and blood oxygenation samples; only data meeting the criteria is used. Based on the sampled data, the heart rate and blood oxygenation values ​​are calculated and displayed on an OLED screen along with their waveforms. Blood oxygenation measurement is mainly divided into transmissive and reflective methods, with transmissive methods currently being the mainstream, although their principles are similar. Both use light-emitting diodes (RED, IR, GREEN, and BLUE, etc.) to illuminate the measured area, and then a photodiode receives the transmitted/reflected light, converting the light signal into an electrical signal. A high-precision ADC then measures the reflected current to assess the oxygen content in the blood. The principle can be simplified as: light --> analog signal --> digital signal. Therefore, we need to control the current intensity and sampling rate of the LED light source, as well as the ADC accuracy (xbit) of the photosensitive sensor. This design is compact, lightweight, simple, and intuitive. Its watch-style design makes it easy to carry, and its high-frequency sampling sensor provides accurate data. An independent rechargeable lithium battery eliminates the hassle of cables. In short, this design has strong practical applications.

PDF_Heart Rate and Blood Oxygen Detection.zip

Altium_Heart Rate & Blood Oxygen Detection.zip

PADS_Heart Rate & Blood Oxygen Detection.zip

BOM_Heart Rate and Blood Oxygen Detection.xlsx

96841

[Verified] QSL card with clock

The front features a digital display clock, and the back contains a QSL card.

I wanted to make a different kind of QSL card with a clock on a PCBA
. I need to constantly check the time during communication, and considering my previous experience with ESP8266 NTP clocks, I designed this.
Regarding the color silkscreen
verification board, to save costs, the size is kept under 1010 pixels and color silkscreening is not used. The original design was approximately 11.575cm in size, and 5 pieces cost 35 yuan.
The hardware and software are now working, and we can order the color silkscreened version.
Why does your QSL card design have a gold 5★?
Because I have many card designs. Based on the content of the image, the ease of obtaining (or rather, photographing? For an artist, it's probably the effort spent creating the image?), and the cost (for example, PCBAs are much more expensive than postcards), they are divided into four-star, limited five-star, and permanent five-star.
Communicating with me can get you virtual items… well, I don't know how to name them, but they're basically the kind used for gacha pulls. One of these items can be used for one "card draw" (i.e., applying for a QSL card, or simply a card lottery).
A maximum of 20 draws will yield one five-star card (commonly known as a small pity). If the five-star card obtained this time is not the current featured card, the next five-star card obtained will definitely be the current featured card (commonly known as a large pity).
(For details, please see my webpage or QRZ.com)
The PCB design uses a standard QSL card for
the back
silkscreen. Single-sided layout, no protrusions in the card area. The signature area is between the pins of the digital display. (Wow, OP!)


Standard silkscreen is white, and the card content is filled in with an oil-based pen. Green (or according to your own solder mask color) background, white template, black handwritten text.


White solder mask requires black silkscreen, resulting in white background with black text, regardless of whether the content is printed or handwritten.


Order Notes: Whether you choose color silkscreen or standard silkscreen, the content will display correctly. However, it is recommended to use light-colored solder mask, such as green and white.
The front features
two 0.56-inch digital tubes. One is a standard one, used to display the date (currently MMDD), and the other is the one with a colon indicating the clock, used to display the time.
For some reason, photos of the digital tubes taken with a mobile phone look terrible, even though they appear normal to the naked eye.
An NFC tag can be attached to the right digital tube; scanning it will directly launch Genshin Impact. If the card is shipped overseas, the tag content will be changed to launch the international version of Genshin Impact. The entire project
, excluding the PCBA,
includes the PCBA, code, and a contact webpage.
The support page for this card
(not finished yet, will be updated later)
is coded on GitHub, but generally, you don't need to compile the code yourself; you can just tune parameters via serial port, which is convenient for users who don't know how to code or don't have the necessary environment.
Currently, parameter tuning is possible via serial port; the tuning method will be put on the webpage later. Essentially, entering the `help` command in the serial port will display all available commands and the configuration file format; it's somewhat similar to a shell scripting interface, in my opinion. (When I first wrote this part of the parameter tuning code, I wanted to use a shell-like approach.)
More...?
I posted it in the group, and the members immediately started brainstorming. Some suggested solar panels, some suggested e-ink screens, but I think that having an onboard lithium battery would be the simplest (and most practical) solution. So, maybe in my next life, I'll add a lithium battery charging and discharging circuit to this thing.

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PDF_【Verified】QSL Card with Clock.zip

Altium_【Verified】QSL Card with Clock.zip

PADS_【Verified】QSL Card with Clock.zip

BOM_【Verified】QSL Card with Clock.xlsx

96844

electronic