text: var usonic = require("r-pi-usonic");
  
  TRIG = 21;
  ECHO = 20;
  MEASUREMENT_TIMEOUT = 750;
  MEASUREMENT_INTERVAL = 2000;
  
  usonic.init(function (error) {
      if (error) {
         	console.log("Init error.");
      } else {
  	console.log("No error.");
  	var sensor = usonic.createSensor(ECHO, TRIG, MEASUREMENT_TIMEOUT);
  	
  	setInterval(function() {
  		var distance = sensor();
  		console.log(distance);
  	},MEASUREMENT_INTERVAL);
      }
  });
  
  setTimeout(function(){
  	MEASUREMENT_INTERVAL = 500;
  	console.log("Measurment Interval adjusted");
  },10000);
  