Baby shaker bluetooth control board development

The opening of the two-child policy has greatly increased the proportion of newborns in the country's population, and people's demand for cribs has increased accordingly. Therefore, the baby rocker can provide a good sleeping and growing environment for babies. The air quality around the crib is a key factor that affects the growth of children at all times. How to monitor the changes in air quality in real time has become an annoyance for parents; if the baby wakes up in the middle of the night, if it is not comforted in time, the cry will be comforted. It is possible to stop after a long time, but finding and responding to babies in time is another worry for parents.

This design is designed to monitor the environment around the crib. When the detection of harmful gases in the air exceeds the standard, the parents will be alerted in real time; the decibel value of the child's environment will be detected at all times, and the music will be played in time and the bed will respond to comfort the child, reducing the risk of parents. number of wake-ups at night.

1. The overall scheme design of the baby rocker

This design uses AU6210K as the main control chip and connects six modules to realize system functions: ①power module; ②Bluetooth module; ③swing drive circuit module; ④sound sensor module; ⑤music player module; ⑥air quality detection module.

2. The hardware circuit design of baby rocking bed

2.1 Selection of main control chip

The main control chip designed is AU6210K, which has multi-application, high-performance audio SOC chip, has a file system that can read MP3 format, and also has MP3 decoding module, supports UFO equipment power-off memory, IO port multiplexing and other functions, suitable for Realize the connection of multi-function modules, which can meet the requirements of Bluetooth access and low power consumption.

2.2 The peripheral connection module design of the main control chip

(1) Power module: The design core of the power module is low power consumption, while ensuring the energy supply of the function. AU6210K contains LDO module, which needs to provide a set of 3.35-5.5V input power supply. When the input voltage is 5V, the power consumption is relatively low. When the system is not in use, the main control board will stop working, enter the low power mode, run the clock alarm with low power consumption, wait for and respond to the wake-up signal in real time. Generally, the Bluetooth module is in the standby state until the main control board wakes up the Bluetooth module and enters the Bluetooth mode.

(2) Sound sensor module: This module adopts a sound detection sensor with reasonable settings and high resolution. The sound detection frame is used to shield the surrounding noise outside the detection hole in the lower part. After differential processing by the processor, the detected The detection of the sound level of the detection object has good detection effect and low production cost. It is designed to detect the noise of the infant's environment and the crying sound of the infant itself. Pass the collected value to AU6210K and decode it to judge whether the baby is crying or not.

(3) Bluetooth module: Connect multiple pins of the Bluetooth chip to the main control AU6210K to realize connection control. After turning on the Bluetooth mode, it will automatically connect to the last connected device, which is convenient for operation, and can directly control the playback on the mobile device, which is convenient for parents to operate.

(4) Rocking drive circuit module: According to the result of decibel detection, it is judged whether to start the mechanism of the rocking bed. If the baby’s crying does not stop under constant reassurance, it will slow down until it stops shaking, and send a message to the parent’s mobile terminal, prompting Parents come to check on the baby's condition. This design uses a radio-controlled electromagnetic rocker, which can adjust the frequency at any time. It is safe, reliable, new and noiseless, and has low production cost.

The design of this part utilizes the principle of electromagnetic induction. The principle of electromagnetic induction is to generate magnetic force after electrifying the coil. The magnitude of the magnetic force is changed by changing the magnitude of the current passing through the coil. During the rocking process, the strength of the rocking table can be adjusted by changing the magnitude of the voltage according to the demand, so that the rocking table can produce a proper and regular swing. Since the current changes linearly, The shaker can rock smoothly with less noise.

(5) Music player module: use the MP3 decoder of the AU6210K function module to take out the MP3 music files from the direct storage, and interpret the signals in the storage in the decoding chip, decode the signals, and then use the digital-to-analog converter to convert these The digital signal is converted into an analog signal, and then the converted analog audio is amplified through the power amplifier module, and finally filtered and then sent to the speaker to play the lullaby stored in advance by the parents.

At the same time, in the bluetooth mode, you can connect the parent's mobile device through bluetooth, and directly control the playback of media music in the device.

(6) Air quality detection module: Three sensors are used in the design to detect air quality: formaldehyde sensor; NH3 sensor; benzene sensor. The formaldehyde sensor adopts the electrochemical sensor CH2O/S-10-S produced by Membrapor to collect the formaldehyde concentration value in the air; the NH3 sensor and the benzene sensor both select the electrochemical sensor produced by Winsensor. The weak current signal corresponding to the gas concentration collected by the gas sensor is output to the main control chip by using the signal conditioning circuit and the FPGA-based analog-to-digital conversion circuit to obtain the initial concentration value of the corresponding gas.

Judging the collected data, when the threshold is exceeded, the alarm function will be triggered, the Bluetooth module will be activated, and an alarm message will be sent to the parent's mobile device.

3. Software design of baby cradle

The design software is written in C language, compiled with KeilμVision5 software, and a while loop is used in the main function. In terms of main function design, system initialization is carried out first.

(1) Judging the value collected by the sound sensor: According to the value returned by the sound sensor, judge whether the baby is crying or not. When the newborn is in a crying state, wake up the Bluetooth mode and start the timer, and drive the music player module and the shaker mechanism at the same time, adjust the music and shaker speed with a suitable volume and gear speed, and at the same time according to the value of the timer It judges whether the crying duration of children reaches the threshold, and sends warning information to guardians through Bluetooth in time. When it is judged that the baby has stopped crying, the rocking bed and music fade out and enter the low battery mode. At the same time, the Bluetooth sleeps, the system is refreshed, and the value of the sensor is re-judged.

(2) Judging the value collected by the air quality sensor: based on the value returned by the air quality sensor, the air quality of the indoor environment where the infant is located is detected. Send a warning message to report the air quality of the child's environment to the parents at this time, and remind the parents to ventilate in time.

Summarize

The main functions realized by this intelligent baby shaker design are: ① real-time detection of the air quality of the environment; ② detection of the crying state of the baby through the sound sensor; ③ control of music playback and control of the shaker through the host computer or Bluetooth; ④ with The function of alerting the mobile terminal via Bluetooth.

The above is the baby rocker development example introduced by Shenzhen Zuchuang Microelectronics Co., Ltd. for you. If you have the development needs of baby rocker solutions, you can rest assured to entrust it to us. We represent a variety of single-chip microcomputers, voice chips, dual-mode Bluetooth ICs, and wifi chips. Brands include Songhan MCU, Yingguang MCU, Jerry Bluetooth, Ankai Bluetooth, Allwinner, and Realtek. Our technical services include: PCB design, microcontroller development, Bluetooth solutions, software and hardware custom development, APP development, small program development, WeChat official account development, etc. It can also undertake the design of intelligent electronic products, the development of living appliances, the research and development of beauty equipment, the application of Internet of things platform, the smart home control system, the development of TWS earphones, Bluetooth earphone speakers, the development of children's educational toys, the design of electronic education products, etc.