stm32血压计的设计

elsaflower 发表于 2024-11-18 09:49

来一套stm32血压计的设计，使用示波法测量，下降趋势。测量周期为20s内，最好能够输出测量的波形

咕咕呱呱孤寡 发表于 2024-11-30 15:51

可以在外包板块找

gaochy1126 发表于 2024-11-30 21:17

stm32血压计的设计

#include "stm32f4xx.h"                // Device header
#include "Handlers.h"
#include "LCDHD44780NonBlocking.h"
#include "BloodPressureMeterFunctions.h"
#include "PressureSensorABPMANN005PG2A3.h"
#include "FIRbandpass_3_10_Hz_Coeff.h"
#include "FIRfilterPtByPt.h"
#include "IIRfilterPtByPt.h"

/*=================================
Formula for pressure calculation:

pressure = ((Output - 1638) * 5)/(14745 - 1638)

1 psi = 51.7149326 mmHg
3.480619445 psi = 180 mmHg

10762 = 180 mmHg
//================================*/

//===Instances of structures and pointers to structures===//
pulseWave__pulseWave;
pulseWave_* pulseWave = &_pulseWave;

FIRfilterObject _BandpassFIRfilter;
FIRfilterObject* BandpassFIRfilter = &_BandpassFIRfilter;
IIR4thOrderFilterObj _LowpassIIRfilter;
IIR4thOrderFilterObj* LowpassIIRfilter = &_LowpassIIRfilter;

//=== Extern variables enabling calculations and display===//
extern volatile uint8_t calculate;
extern volatile uint8_t displayOnLCDevery1sec;
extern volatile uint8_t displayOnLCDevery250milisec;

//===========FIR filter coefficients===========//
extern float FIRbandpass_3_10_Hz_Coeff;

//==== Circular buffers to pass into FIRfilterObject ===//
float signalBufferForBandpassFIRfilter;

int main()
{
RCCClockConfiguration();
/* FPU initialization */
SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2));/* set CP10 and CP11 Full Access */

PumpValveButtonConfiguration();
LCDInitialize();
TimersInitialization();

LCDLocateXY(0,0);
LCDSendText("Put cuff on arm ");
LCDLocateXY(0,1);
LCDSendText("pressbutton ");
PressureSensorInitialize();

//====== Initialization of pointers ======//
float LPFiltered;
float BPFiltered;
float* lowPassFiltered;
float* bandPassFiltered;
lowPassFiltered = &LPFiltered;
bandPassFiltered = &BPFiltered;
//==============================//

volatile float previousValue, derivative, previousDerivative;             // Variables for determining change of 1st derivative sign of lowpass filtered output
volatile float previousValueBP, derivativeBP, previousDerivativeBP;// Variables for determining change of 1st derivative sign of bandpass filtered output

_BandpassFIRfilter = CreateFIRfilterObject(256, signalBufferForBandpassFIRfilter, 166, FIRbandpass_3_10_Hz_Coeff);
_LowpassIIRfilter = IIR_4thOrderSignalFilteringPtByPtInitialize(IIRforwardCoeffLowpass_20Hz, IIRreverseCoeffLowpass_20Hz);

unsigned int BPfilterDelay = (unsigned int) (_BandpassFIRfilter.coefficientsLength - 1) / 2; //Length of bandpass FIR filter group delay

volatile uint8_t displayHeart = 0;    //Variable controlling display of heart character on LCD
volatile uint8_t clearHeart = 0;       //Variable controlling clear of heart character on LCD
volatile uint8_t calculateMAP = 0; //Variable controlling start of MAP evaluation

while(1)
{
if(calculate)
{
if( pressureArrayHead != pressureArrayTail)
{
//======================= Filtration of data from pressure sensor ========================//
   IIR_4thOrderSignalFilteringPtByPt(LowpassIIRfilter, pressureArray, lowPassFiltered);
FIRfilterPtByPt(BandpassFIRfilter, pressureArray, bandPassFiltered);

//=======================Update of buffers and variables values========================//
pulseWave->currentPressure = ((*lowPassFiltered- 1638.0f) * 5.0f) / (14745.0f - 1638.0f) * 52.0f;
pulseWave->numberOfSamples++;
Last128SamplesBufferHead = (Last128SamplesBufferHead+1) & 127;
   Last128SamplesBuffer = *lowPassFiltered;
   pressureArrayTail = (pressureArrayTail + 1) & pressureArrayMask;

//=======New derivative value calculation=======//
derivative = *lowPassFiltered - previousValue;
derivativeBP = *bandPassFiltered - previousValueBP;

   //====================== Peak detection ======================//
if( ((derivative * previousDerivative) < 0) && ((derivative - previousDerivative) < 0) )
{
if((pulseWave->numberOfSamples - pulseWave->previousPeakXcoordinate ) > 64)// if two Peaks distance > approximate 250 ms
{
displayHeart = 1;
pulseWave->previousPeakXcoordinate = pulseWave->numberOfSamples;
}

if( ! pulseWave->systolicPressure )
{
calculateMAP = 1; // if Systolic peak detected start evaluating MAP
pulseWave->systolicPressure = pulseWave->currentPressure;
}
}

//======================== MAP calculation =========================//
if( calculateMAP )
{
if( ((derivativeBP * previousDerivativeBP) < 0) && ((derivativeBP - previousDerivativeBP) < 0) )
{
if( *bandPassFiltered > pulseWave->workingMAPpressure )
{
pulseWave->MAPpressure = ((Last128SamplesBuffer[(Last128SamplesBufferHead - BPfilterDelay) & 127] - 1638.0f) * 5.0f) / (14745.0f - 1638.0f) * 52.0f;
pulseWave->workingMAPpressure = *bandPassFiltered;
}
}
}

//============Variables update=============//
previousDerivative = derivative;
previousValue = *lowPassFiltered;
previousDerivativeBP = derivativeBP;
previousValueBP = *bandPassFiltered;

//============Ending calculations==============//
if( pulseWave->currentPressure < 50 )
{
LCDLocateXY(0,0);
LCDSendText("SYS:");
LCDLocateXY(7,0);
LCDSendData(' ');
LCDLocateXY(8,0);
LCDSendText("DIA:");

calculate = 0;
calculateMAP = 0;
TIM4->CR1 &= ~TIM_CR1_CEN;// Turn off Timer controlling displaying on LCD
displayOnLCDevery1sec = 0;
displayOnLCDevery250milisec = 0;
pulseWave->diastolicPressure = ( pulseWave->MAPpressure * 3 - pulseWave->systolicPressure ) / 2 ;

LCDLocateXY(4,0);
LCDSend8bitInteger((uint8_t) pulseWave->systolicPressure);

LCDLocateXY(12,0);
LCDSend8bitInteger((uint8_t) pulseWave->diastolicPressure);

LCDLocateXY(0,1);
LCDSendText("MAP:");

LCDLocateXY(6,1);
LCDSend8bitInteger((uint8_t) pulseWave->MAPpressure);

LCDLocateXY(12,1);
LCDSendText(" ");
}
}
}
else
{
if( pressureArrayHead != pressureArrayTail)
{
//======================= Filtration of data from pressure sensor ========================//
         IIR_4thOrderSignalFilteringPtByPt(LowpassIIRfilter, pressureArray, lowPassFiltered);
FIRfilterPtByPt(BandpassFIRfilter, pressureArray, bandPassFiltered);

//=======================Update of buffers and variables values========================//
Last128SamplesBufferHead = (Last128SamplesBufferHead+1) & 127;
Last128SamplesBuffer = *lowPassFiltered;
   pressureArrayTail = (pressureArrayTail + 1) & pressureArrayMask;

   pulseWave->currentPressure = ((*lowPassFiltered- 1638.0f) * 5.0f) / (14745.0f - 1638.0f) * 52.0f;
   previousDerivative = *lowPassFiltered - previousValue;
      previousDerivativeBP = *bandPassFiltered - previousValueBP;
      previousValue = *lowPassFiltered;
      previousValueBP = *bandPassFiltered;
}
}

if(displayOnLCDevery250milisec)
{
if(clearHeart)
{
LCDLocateXY(8,0);
LCDSendData(' ');
clearHeart = 0;
}

if(displayHeart)
{
LCDLocateXY(8,0);
LCDSendData(heart);
displayHeart = 0;
clearHeart = 1;
}

displayOnLCDevery250milisec = 0;
}

if(displayOnLCDevery1sec)
{
LCDLocateXY(12,1);
LCDSend8bitInteger((uint8_t) pulseWave->currentPressure);

displayOnLCDevery1sec = 0;
}
}
}

gaochy1126 发表于 2024-11-30 21:21

stm32血压计的设计

硬件和原理图，私信我。

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stm32血压计的设计

stm32血压计的设计

stm32血压计的设计