Today brought a set of Bluetooth 4.2 module application in the design of smart Bluetooth heart rate monitor design . Â
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First, the main hardware components involved in the Bluetooth heart rate tester : Â Â Â Â
The hardware structure includes signal acquisition, Bluetooth 4. 2 module for wireless data transmission, data display , battery power and management, ultra-low power three-axis accelerometer.
(1) LED Display Screen: display the calculated heart rate
(2) Polymer lithium battery pack: power the system, including Bluetooth module, 3- axis accelerometer , LED display, heart rate sensor, etc.
(3) Heart rate sensor: mainly responsible for the collection of heart rate signals
(4) Ultra-low power three-axis accelerometer : system error compensation
(5) Bluetooth 4. 2 module SKB369
This program uses the SKB369 Bluetooth serial port module, based on the nRF52832 Bluetooth chip.
Bluetooth version: based on ble low power Bluetooth 4.2 development, support for Bluetooth 5.0 (firmware upgrade)
Chip: Nodic nRF52832
Data transfer rate: 1Mbps
Antenna: PCB onboard antenna
Size: 17.4*13.7*1.9mm
Transmission distance: 100 meters
Working voltage: 2.4-3.6V
Working temperature: -40~85°C
Rich interface: Provide flexible hardware interface, support GPIO , IIC , SPI , UART , ADC and other interfaces, making the application of Bluetooth module more flexible!
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Second, based on the Bluetooth 4.2 module Intelligent Bluetooth heart rate monitor application framework:
In the scheme, the heart rate sensor is used to collect heart rate information in real time, and the collected heart rate data is transmitted to the main control MCU of the Bluetooth module SKB369 , and the heart rate value is calculated by the MCU , and the heart rate value can be displayed on the LED screen through the corresponding interface on the other hand; also the heart rate data can be transparently transmitted through SKB369 to the phone app, cell phone app is responsible for receiving and analyzing the received heart rate data, enabling real-time monitoring of heart rate values in the mobile phone side.
Because of the small size of the Bluetooth heart rate monitor system, it can be worn as a wearable device to monitor anytime, anywhere. Considering that the collected signal is susceptible to errors caused by human motion interference , a 3- axis accelerometer is added to the design to obtain motion artifact noise for further processing .
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Third, the advantages of this Bluetooth heart rate monitor design ideas:
This design idea applies the real-time transmission, automatic detection and real-time feedback function of Bluetooth 4.2 module to heart rate detection, which has the following advantages:
( 1 ) accurate measurement, very good real-time
( 2 ) Small size and low power consumption
( 3 ) Low cost, can be made into wearable devices
This smart Bluetooth heart rate monitor is suitable for everyday use or as a wearable heart rate detection device.
Yuhai Company is engaged to research and development of piezoelectric products and related piezoelectric products, the related piezoelectric products includes the piezo sensors and transducer.
The ultrasonic transducer is a kind of transducer that converts the ultrasonic signal into electric signal, or vice versa. Ultrasound transmitter and receiver is a transducer that can transmit and receive ultrasound. Ultrasound sensor is a kind of sensor, in essence, it is also a transmitter and receiver. The working principle of this kind of equipment is similar to that of radar and sonar. Active ultrasonic sensors can emit and receive reflected waves, and determine the distance of the target by measuring the time interval between transmission and reception. Passive ultrasonic sensor is actually a microphone that can convert ultrasonic signal into electrical signal.
According to the working principle and materials used, the ultrasonic transducer has piezoelectric transducer, electrostatic transducer (capacitive transducer), magnetostrictive transducer, electromagnetic acoustic transducer, mechanical transducer and other types [1].
Ultrasonic Sensor,Piezo Sensor,Ultrasonic Piezo Disc,Ultrasonic Piezo Elements
Zibo Yuhai Electronic Ceramic Co., Ltd. , https://www.yhpiezo.com