Added applied robotics code to archive.

OSU Coursework/ROB 421 - Applied Robotics/software/firmware/sensor_demo/sensor_demo.ino

@@ -0,0 +1,148 @@
+#define PRESSURE_INPUT_PIN A5
+#define VALVE_CONTROL_PIN 9
+#define COMPRESSOR_CONTROL_PIN 2
+
+#define LED_PIN 13
+
+//Code safeties
+#define SAFETY_PSI_MAX 25
+
+String input;
+
+void setup() {
+
+  pinMode(COMPRESSOR_CONTROL_PIN, OUTPUT);
+  digitalWrite(COMPRESSOR_CONTROL_PIN, LOW);
+  pinMode(LED_PIN, OUTPUT);
+  digitalWrite(LED_PIN, LOW);
+  pinMode(PRESSURE_INPUT_PIN, INPUT);
+
+  pinMode(VALVE_CONTROL_PIN, OUTPUT);
+  digitalWrite(VALVE_CONTROL_PIN, HIGH);
+
+  Serial.begin(9600);
+}
+
+void loop() {
+  uint16_t targetPSI = 0;
+  float    currentPSI = 0;
+  uint8_t  shouldCompress = 0;
+  digitalWrite(VALVE_CONTROL_PIN, HIGH) ;
+  
+  if(Serial.available()){
+    input = Serial.readStringUntil('\n');
+    Serial.flush();
+
+    if(isValidNumber(input)){
+      targetPSI = input.toInt();
+      
+      Serial.print("Target PSI: ");
+      Serial.println(targetPSI);
+
+      if(targetPSI > SAFETY_PSI_MAX){
+        Serial.print("Target PSI too high, bounding to safety max of ");
+        Serial.println(SAFETY_PSI_MAX);
+      }
+
+      targetPSI = constrain(targetPSI, 0, SAFETY_PSI_MAX);
+      
+      shouldCompress = 1;
+
+      //Start the compressor
+      digitalWrite(COMPRESSOR_CONTROL_PIN, HIGH);
+      digitalWrite(LED_PIN, HIGH);
+
+      while(shouldCompress){
+        currentPSI = readPressure();
+        if(currentPSI >= targetPSI){
+          shouldCompress = 0;
+        }
+        Serial.print("Current Pressure: ");
+        Serial.print(currentPSI);
+        Serial.print(" psi | Target Pressure: ");
+        Serial.print(targetPSI);
+        Serial.println(" psi");
+        delay(150);
+      }
+
+      //Stop the compressor
+      digitalWrite(COMPRESSOR_CONTROL_PIN, LOW);
+      digitalWrite(LED_PIN, LOW);
+
+      //Wait for half a second
+      delay(500) ;
+      //Release Valve
+      digitalWrite(VALVE_CONTROL_PIN, LOW) ;
+      //Wait to let all the pressure out
+      delay(2500) ;
+    }
+    
+  }
+
+  delay(150);  // ¯\_(ツ)_/¯
+
+  Serial.print("Current Pressure: ");
+  Serial.print(readPressure());
+  Serial.println(" psi");
+  Serial.flush();
+
+
+  /*
+  //Turn off the compressor
+  digitalWrite(COMPRESSOR_CONTROL_PIN, LOW);
+  digitalWrite(LED_PIN, LOW);
+  for(int i = 0; i < 2; ++i){
+    delay(160);
+    Serial.print("Read Analog Value: ");
+    Serial.print(readPressure());
+    Serial.println(" psi");
+    Serial.flush();
+  }
+
+  */
+
+  /*
+  //Turn on the compressor
+  digitalWrite(COMPRESSOR_CONTROL_PIN, HIGH);
+  digitalWrite(LED_PIN, HIGH);
+  for(int i = 0; i < 6; ++i){
+    delay(160);
+    Serial.print("Read Analog Value: ");
+    Serial.print(readPressure());
+    Serial.println(" psi");
+    Serial.flush();
+  }
+  */
+
+
+}
+
+/*
+ * 
+ * Pressure is a signal from 1 - 5 volts with 5 volts signifying 1 MPa 
+ * See http://nickmccomb.ddns.net:8090/display/AR/Sensors#Sensors-ISE50-T2-62L
+ */
+float readPressure(){
+  analogRead(PRESSURE_INPUT_PIN);
+  uint16_t raw_adc = analogRead(PRESSURE_INPUT_PIN);
+
+  float voltage = 0.004887585532746823 * (float) raw_adc;  //ADC count (10 bit) to voltage conversion
+
+  float pressure = (250000.0 * voltage -250000.0) * 0.000145038; //Convert voltage to pascals, then to PSI
+
+  return pressure;
+}
+
+
+boolean isValidNumber(String str){
+   for(byte i=0;i<str.length();i++)
+   {
+      if(isDigit(str.charAt(i))) return true;
+        }
+   return false;
+} 
+
+
+
+
+