Sensors employed in the robot

1. Ultrasonic Sensor for EV3:
   The digital EV3 Ultrasonic Sensor generates sound waves and reads their echoes to detect and measure distance from objects. It can also send single sound waves to work as sonar or listen for a sound wave that triggers the start of a program. Basically, Ultrasonic sensors work by emitting sound waves at a frequency too high for humans to hear. They then wait for the sound to be reflected back, calculating distance based on the time required.
   This is similar to how radar measures the time it takes a radio wave to return after hitting an object.Below are a few advantages of ultrasonic sensors:
   *Not affected by color or transparency of objects
   *The ultrasonic sensor for Lego Mindstorms EV3 robots can also work as a simple emitter to signal its presence to other
   robots for example or as simple receiver to react to the presence of an ultrasonic wave.
   *The ultrasonic sensor for Lego Mindstorms EV3 robots can compute distances between 1 and 250 cm with a precision around the centimeter.
   It has leds that are on when the sensor emits and blink when the sensor is listening.

2. Gyroscope Sensor for EV3:
   The digital EV3 Gyro Sensor measures the robot’s rotational motion and changes in its orientation. If the gyro sensor is rotated in the direction of the arrows on case of the sensor, the sensor can detect the rate of rotation in degrees per second. In addition to this, the gyro sensor keeps track of the total rotation angle in degrees.In our project, this information is combined with with the information from ultrasonic sensor to determine the location of the objects and obstacles. The detailed formula is explained
   in the respective section.

3. Color Sensor for EV3: The color sensor is a digital sensor that can detect the color or intensity of light that enters the small window on the face of the sensor. The digital EV3 Color Sensor distinguishes between seven different colors and can also detect the absence of color. It also serves as a light sensor by detecting light intensities. However, in our robot design, we are not using this though its present for two reasons:
   • We already are reaching the defined objectives through our gyro sensor and the ultrasound sensor. Hence, this will be an unecessay addition.
   • The color sensor accuracy is good only at a short distance that too with an additional light sensor. The risk is that to reach the required distance, we may have to move too close to the obstacle and
     if touched, we lose a point. Hence, color sensor is not being used.