Calculating Distance Using Pi, Diameter, and Degrees


Click Here for Printable Worksheet #1


Click Here for Printable Worksheet #2



Use the constant Pi (3.14) and Diameter measurements to calculate the degrees needed to rotate wheels to move the robot a set distance or make accurate turns. 

Two numbers to know when calculating distance and degrees:

Diameter of NXT Wheel
Distance between Wheels




Key Formulas:

Circumference = Pi x Diameter

C = 3.14 * D
C = 3.14 * 56 mm


Distance / Circumference = Rotations

D
--  =  R
C

Degrees = Rotations x 360

Deg = R x 360


Exercise 1: Given the Diameter of a Mindstorms NXT Robot Tire, calculate the number of degrees rotation needed to travel 60 centimeters.


(Diameter of Mindstorms Robot Tire = 56 millimeters)

Circumference =   3.14  *  __________________  (Diameter)

Circumference =    _________________________

Distance / Circumference = Rotations

__________  / ____________  =  _____________

Degrees = Rotations * 360

_______  = _________  * 360

Degrees = __________



Exercise 2:  Given the Diameter of a Mindstorms NXT Robot Tire and the distance between the two wheels, calculate the degrees rotation needed to make the robot do a Swing Turn of 90 degrees.



(Diameter of Mindstorms Robot Tire = 56 millimeters)
(Distance between Robot wheels = ? -> You will need to measure)

(Diameter of Mindstorms Robot Tire = 56 millimeters)

Circumference of Tire =   3.14  *  __________________  (Diameter)

Circumference of Tire = _________________________

90 Degree Swing Turn = 1/4 of Circle Created by robot swinging around on tire. 

Diameter of Robot Circle = Distance Between Wheels * 2

Circumference of Robot Circle = 3.14 * Distance Between Robot Wheels * 2

_______________________  =  3.14 * _________________________ * 2

Circumference of Robot Circle / 4 = Distance Wheel needs to travel.

________________________ / 4 = Distance Wheel needs to travel.

_________________________ = Distance Wheel needs to travel

Distance Wheel needs to travel / Diameter of Wheel = Rotations

_________________________ / ________________  = Rotations

Rotations = ___________________

Rotations * 360 = Degrees

__________  * ___________ = ____________ 

Degrees = ______________


Exercise 3: Given the Diameter of a Mindstorms NXT Robot Tire and the distance between the two wheels, calculate the degrees rotation needed to make the robot do a Point Turn of 90 degrees.



(Diameter of Mindstorms Robot Tire = 56 millimeters)

Circumference of Tire =   3.14  *  __________________  (Diameter)

Circumference of Tire = _________________________

90 Degree Swing Turn = 1/4 of Circle Created by robot turning both wheels in opposite directions. 

Diameter of Robot Circle = Distance Between Wheels

Circumference of Robot Circle = 3.14 * Distance Between Robot Wheels

_______________________  =  3.14 * _________________________

Circumference of Robot Circle / 4 = Distance Wheel needs to travel.

________________________ / 4 = Distance Wheel needs to travel.

_________________________ = Distance Wheel needs to travel

Distance Wheel needs to travel / Diameter of Wheel = Rotations

_________________________ / ________________  = Rotations

Rotations = ___________________

Rotations * 360 = Degrees

__________  * ___________ = ____________ 

Degrees = ______________

(Both wheels need to turn these degrees in opposite directions.)