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## For our robot with one ultrasound sensor – determine the distance error at its final destination point (B) after 4 turns, if the room temperature varies from 70 to 80 degree Fahrenheit. Reduce the error to an absolute minimum. If the counter inside of the microcontroller counts up once every microsecond, what would be the count of the timer when the robot is at point B? You are welcome to add your own methods on how to reduce the error further

15 Feb

The count of the timer on our computer records how many turns per second the wheels of the robot make. To find the count of the wheels in our robot, first find the circumference of the wheel by multiplying 6.5 by pi, which equals approximately 20 cm. We are given that one turn takes 3 seconds. If the robot travels 20 cm in one turn, then the speed is 20 cm per 3 seconds. This estimates to about 7 cm per second. The total distance from point A to point B is 80 cm. Therefore, by dividing 80 by 7, the final answer is about 11.4 seconds. This is the time it takes the robot to go from point A to point B.

In order to find the percent of error, we used the formula Cair = 331.5 + (0.6× Tc ) m/s in which Tc is the air temperature in Celsius and Cair is the speed of sound. First convert 70 and 80 degrees Fahrenheit into Celsius which would equal to 21.11 and 26.6 respectively. Plug in each of these numbers separately into the equation as Tc. When you plug in 21.11 into the equation, the result is 344.166. After, multiply by 344.166 by 100 to convert from meters to cm per sec. Then, repeat the same process for 26.66. The result should be 347.46 in which should be multiplied by 100. To find the percent of error, subtract 34416.6 from 34746 which equals approximately 329. Then, divide this number by 80 to find the percentage. The resulting number is 4.1125. To reduce this error, reduce the range of temperatures in the surrounding environment.