Whittier Elementary Science Fair

Last week Whittier Elementary had a science fair, and a few of us Technically Learning folks went along to help demo some LEGO robotics. Our goals were to show off the great work that some of the students have been doing and to get more students, parents, and teachers interested in using these robots as a learning tool. The school gym was jam packed with hundreds of people eating ice cream from the Ice Cream Social and checking out all the science project posters. We were literally up on center stage, with several robots running around. The line-following robot was a big hit, as was the gear demo that used color wheels. Several of the older students were working on fun little robots to avoid walls using distance sensors and to turn around exactly 180 degrees and come back to them. I had a fun time, even though talking to some many people and trying to keep up with the kids tired me out a bit. I do enjoy watching the students interact with the robots and get excited about problem solving. It's fun to see them figure out how the robot works. Their eyes just light up with the discovery. And you have to love science fairs. Anything that stresses the importance of science to a solid education is alright by me.

Robot Olympics!

We’re busy creating another exciting activity guide; right now it’s in the “preliminary draft” stage now, but I wanted to give you a sneak peak at what’s to come. The Robot Olympics is a fun, math centric activity guide in which kids can build LEGO robotics and compete to build the best performing design.

Here’s a list of the events we’ve come up with, of course we’d love to hear your input as well.

1. Trace the Race Course – Build a car that can measure the perimeter of a complex shaped off-road race course by calculating the speed of a line-following robot.


2. Wheel Circumference - Measure the diameter of the car’s wheel and calculate the circumference. Then calculate the circumference by measuring the distance it travels and the number of wheel rotations. Discuss the accuracy of each method.


3. Slowest Car – Build the slowest car using different gearing ratios, and wheels.


4. Soccer Bot - Build a robot capable of “kicking” a ball into a goal.


5. Spy Olympics: Crack the Code - Figure out other groups’ Secret Number using graphing, probability and averages


6. Olympic Rope Climbing - Build a car that can climb a rope by reeling itself up a piece of string.


7. Steep Ramp - Build a robot that climbs the steepest ramp.
   Fast Car Race – Use gearing ratios and different wheels to build the car that can go the fastest!


8. OLYMPICS! – A final Olympics Competition that includes four different competitions: a Tug of war Contest, a Contest to build a car the travels a very specific distance, a Robot that can throw a ball into a basket, and an off road race.

Here’s one of my favorites, the Soccer Bot:

Goal:

To build a robot capable of “kicking” one of the colored plastic balls into a goal. Then calculate its probability of making the goal at different distances.

Main Themes:

• Probability and percentage
  
• Robotic aim and accuracy

Math Theory:
Probability is the chance that an event will occur in the future, based on past behaviors. The probability of your soccer bot making the next shot is the number of goals your robot has already made out of the total shots it has taken.
Probability = # of goals / total shots

Percentage is the ratio of goals made to the total shots attempted, expressed in the hundredths.
Percentage = (# of goals / total shots) x 100
Percents are shown with a percentage symbol at the end, for example 100% or 78%.

Activity Instructions:
Pre-activity setup:

• Construct a soccer goal that is about a foot wide. 
  
• It can be made out of cardboard, stacked books, or other construction material. 
  

Day 1

• Build a soccer robot to kick the ball towards a goal. Robots can also throw the ball, hit it like a billiards cue, etc.
  
• Test to make sure it can at least sometimes make the goal at both 3 feet and 10 feet away. 
  

Day 2

• If needed, iterate on the soccer bot design to make the ball go far enough to reach the goal from 10 feet away. 
  
• Test the soccer bot by taking 10 shots at the goal from 3 feet away. 
  
• Record the number of shots successfully made
  
• Calculate the probability of making a future shot from that distance. Represent this as a fraction, and then as a percentage. 
  
• Test the soccer bot by taking 10 shots at the same goal, but this time from 10 feet away.
  
• Record the number of shots successfully made, and calculate the probability of making a future shot from that distance. Represent this as a fraction, and then as a percentage.

Construction Tips:

• Build a solid, sturdy robot! Repeated kicks of the ball will rattle it apart if it’s not strong enough.
  
• There are many styles of ball hitting to mimic, here are just a few:
  
• Kicking with a vertical “leg”, similar to a human kicking or a pendulum swinging.
• Hitting the ball sideways, like pinball flippers
  
• Hitting the ball straight on, like a billiard/pool cue
  
• Throw the ball, as a human (or catapult) would
  
• Either a motor powered kicker or a spring loaded system can be used.

Discussion Questions:

• Did your robot have a higher probability of making the goal at 3 feet or 10 feet? Why? How much of a difference was there?
• How far away do you think the goal would have to be to have a less than 1% probability of making each shot?
  
• What types of robots had the highest probabilities of making each shot?

Activity Variations (optional):

• Iterate the design to make a better robot that has a higher probability of making the goal. This could be easily run as multi-round competition over 3 or more sessions where the students iterate (and document design changes!), improving their robot each session.
• Write journal entries and/or draw diagrams of your initial design, what you changed and why, and your final design.

Resources:
International annual robotic soccer competition: http://www.robocup.org/