add homie and weight filter functions

This commit is contained in:
interfisch 2021-02-21 17:35:18 +01:00
parent 5ae6ab0c02
commit 5a99550e9c
2 changed files with 186 additions and 4 deletions

View File

@ -18,3 +18,4 @@ monitor_speed= 115200
lib_deps =
bogde/HX711 @ 0.7.4
Homie@3.0.0

View File

@ -1,4 +1,14 @@
#include<Arduino.h>
#include <Arduino.h>
#include <Homie.h>
/*
* Wemos d1 mini
* Flash Size: 4M (1M SPIFFS)
*/
//Upload config: platformio run --target uploadfs
#include "HX711.h"
@ -6,10 +16,63 @@
const int LOADCELL_DOUT_PIN = D2;
const int LOADCELL_SCK_PIN = D3;
const int PIN_SELFENABLE = D1;
HX711 scale;
#define MEASURE_INTERVAL 100 //ms
#define READING_FILTER_SIZE 40 //latency is about READING_FILTER_SIZE/2*MEASURE_INTERVAL
float weight_read[READING_FILTER_SIZE] = {0};
uint8_t weight_read_pos=0;
#define MEANVALUECOUNT 4 //0<= meanvaluecount < READING_FILTER_SIZE/2
float weight_tare=0; //minimal filtered weight
#define MIN_WEIGHT_DIFFERENCE 50 //minimum weight
float weight_max=0; //max filtered weight
bool weight_sent=false;
unsigned long weight_sent_time=0;
#define MAXONTIME 60000*2 //turn off after ms
#define FW_NAME "scale"
#define FW_VERSION "0.0.1"
void loopHandler();
HomieNode scaleNode("weight", "Scale", "scale"); //paramters: topic, $name, $type
int sort_desc(const void *cmp1, const void *cmp2);
float getFilteredWeight();
float getWeightSpread();
void sendWeight(float w);
void setup() {
pinMode(PIN_SELFENABLE,OUTPUT);
digitalWrite(PIN_SELFENABLE, HIGH);
pinMode(LED_BUILTIN,OUTPUT);
digitalWrite(LED_BUILTIN, HIGH);
Serial.begin(115200);
Homie.disableResetTrigger(); //disable config reset if pin 1 (D3) is low on startup
Homie_setFirmware(FW_NAME, FW_VERSION);
Homie_setBrand(FW_NAME);
Homie.setLoopFunction(loopHandler);
scaleNode.advertise("human");
scaleNode.advertise("spread");
scaleNode.advertise("raw");
scaleNode.advertise("max");
Homie.setup();
scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
@ -61,11 +124,78 @@ void setup() {
}
void loop() {
Homie.loop();
}
Serial.print("reading:\t");
Serial.println(scale.get_units(10));
void loopHandler() {
unsigned long loopmillis=millis();
static unsigned long last_measure=0;
if (loopmillis>last_measure+MEASURE_INTERVAL) {
last_measure=loopmillis;
Serial.print("reading=");
float weight_current=0;
if (scale.wait_ready_timeout(1000)) { //for non blocking mode
weight_read_pos++;
weight_read_pos%=READING_FILTER_SIZE;
weight_current=scale.get_units(1);
weight_read[weight_read_pos]=weight_current; //one reading takes 91ms
} else {
Serial.println("HX711 not found.");
}
float weight_filtered=getFilteredWeight();
float spread=getWeightSpread();
Serial.println(weight_current);
Serial.print("spread="); Serial.println(spread,3);
char charBuf[10];
dtostrf(weight_current,4, 3, charBuf);
scaleNode.setProperty("raw").send(charBuf);
dtostrf(spread,4, 3, charBuf);
scaleNode.setProperty("spread").send(charBuf);
#define MAXSPREAD_TARE 0.1 //in kg, for tare can be lower than for measuring
if (spread<MAXSPREAD_TARE) { //if reading is stable
if (weight_filtered<weight_tare) { //new min
weight_tare=weight_filtered;
Serial.print("new tare="); Serial.println(weight_tare,3);
}
}
#define MAXSPREAD_MEASURE 0.5 //in kg
if (spread<MAXSPREAD_MEASURE) { //if reading is stable
if (weight_filtered>weight_max) { //new max
weight_max=weight_filtered;
Serial.print("new max="); Serial.println(weight_max,3);
}
}
dtostrf(weight_max-weight_tare,4, 3, charBuf);
scaleNode.setProperty("max").send(charBuf); //filtered and auto tared
if (!weight_sent) {
if (weight_max-weight_tare>MIN_WEIGHT_DIFFERENCE) {
sendWeight(weight_max-weight_tare);
}
}
}
#define STAYONTIME_AFTER_SENT 5000
if (millis() > MAXONTIME || (weight_sent && millis()>weight_sent_time+STAYONTIME_AFTER_SENT)) {
Serial.println("Turning Off");
Serial.flush();
delay(100);
digitalWrite(PIN_SELFENABLE, LOW);
}
/*
scale.power_down(); // put the ADC in sleep mode
@ -73,3 +203,54 @@ void loop() {
scale.power_up();*/
}
int sort_desc(const void *cmp1, const void *cmp2) //compare function for qsort
{
float a = *((float *)cmp1);
float b = *((float *)cmp2);
return a > b ? -1 : (a < b ? 1 : 0);
}
float getFilteredWeight() {
float copied_values[READING_FILTER_SIZE];
for(int i=0;i<READING_FILTER_SIZE;i++) {
copied_values[i] = weight_read[i]; //TODO: maybe some value filtering/selection here
}
float copied_values_length = sizeof(copied_values) / sizeof(copied_values[0]);
qsort(copied_values, copied_values_length, sizeof(copied_values[0]), sort_desc);
float mean=copied_values[READING_FILTER_SIZE/2];
for (uint8_t i=1; i<=MEANVALUECOUNT;i++) {
mean+=copied_values[READING_FILTER_SIZE/2-i]+copied_values[READING_FILTER_SIZE/2+i]; //add two values around center
}
mean/=(1+MEANVALUECOUNT*2);
return mean;
}
float getWeightSpread() { //absolute difference between lowest and highest value in buffer
float copied_values[READING_FILTER_SIZE];
for(int i=0;i<READING_FILTER_SIZE;i++) {
copied_values[i] = weight_read[i]; //TODO: maybe some value filtering/selection here
}
float copied_values_length = sizeof(copied_values) / sizeof(copied_values[0]);
qsort(copied_values, copied_values_length, sizeof(copied_values[0]), sort_desc);
float diff=copied_values[0]-copied_values[READING_FILTER_SIZE-1];
if (diff<0) { //abs for float
diff*=-1;
}
return diff;
}
void sendWeight(float w) {
char charBuf[10];
dtostrf(w,4, 3, charBuf);
scaleNode.setProperty("human").send(charBuf);
weight_sent=true;
weight_sent_time=millis();
Serial.print("Weight sent="); Serial.println(w,3);
}