Add low voltage warning for DT

Author: srimanachanta

src/main/java/frc/robot/Constants.java

@@ -12,6 +12,8 @@ public class Constants {
 
   public static final double kLoopPeriodSecs = 0.02;
 
+  public static final double LOW_VOLTAGE_WARNING_THRESHOLD = 10.0;
+
   public enum RobotMode {
     REAL,
     SIM,

src/main/java/frc/robot/Robot.java

@@ -13,6 +13,8 @@
 
 package frc.robot;
 
+import edu.wpi.first.math.filter.Debouncer;
+import edu.wpi.first.wpilibj.Alert;
 import edu.wpi.first.wpilibj.DriverStation;
 import edu.wpi.first.wpilibj.RobotController;
 import edu.wpi.first.wpilibj.Threads;
@@ -37,6 +39,10 @@ public class Robot extends LoggedRobot {
   private Command autonomousCommand;
   private final RobotContainer robotContainer;
 
+  private final Alert lowBatteryVoltageAlert =
+      new Alert("Battery voltage is too low, change the battery", Alert.AlertType.kWarning);
+  private final Debouncer batteryVoltageDebouncer = new Debouncer(0.5);
+
   public Robot() {
     super(Constants.kLoopPeriodSecs);
 
@@ -86,6 +92,11 @@ public void robotPeriodic() {
     // Run command scheduler
     CommandScheduler.getInstance().run();
 
+    // Update Battery Voltage Alert
+    lowBatteryVoltageAlert.set(
+        batteryVoltageDebouncer.calculate(
+            RobotController.getBatteryVoltage() <= Constants.LOW_VOLTAGE_WARNING_THRESHOLD));
+
     // Return to normal thread priority
     Threads.setCurrentThreadPriority(false, 10);
   }