Introduction To Robot Decision Making When - after the movement chapter and before the sensor chapter in the curriculum Goal - students to develop a mental model of how robots make decisions The lesson includes: the 6th grade level mathematical concept of inequalities how Boolean expressions use relational operators to make TRUE or FALSE decisions What students know At the end of this lesson students will be able to: Describe what a Boolean expression is Explain how inequalities (a concept taught in 6th grade math classes) are used to form Boolean expressions Teacher background information Boolean expressions Relational operators Example conditional statement Note about Logical Operators Teacher directions to implement the lesson Help students understand what a Boolean expression is Introduce students to the type of sensors that they are using Introduce student to TRUE of FALSE decision making Check students’ understanding of robot decision making Assign students to describe how robots make decisions

How do robots make decisions? 540 mm Evaluate the statements below. What do you notice about them? Be prepared to discuss. “The robot is more than 400mm from the wall” Distance from wall > 500mm Distance from wall == 500mm 400mm > Distance from wall “The robot is 540mm long” Distance from wall == 540mm “The robot is not 540mm from the wall” Distance from wall < 1000mm Ask students to look at the picture and then evaluate the statements in RED.

Discussion What do these statements have in common? Why might it be useful to be able to say whether the robot is more than 500mm from the wall or not? “The robot is more than 400mm from the wall” Distance from wall > 500mm Distance from wall == 500mm 400mm > Distance from wall “The robot is 540mm long” Distance from wall == 540mm “The robot is not 540mm from the wall” Distance from wall < 1000mm Ask students: “What do these statements have in common?” “Why might it be useful to be able to say wheterh the robot is more than 500 mm from the wall or not?” EXPECT ANSWERS LIKE: They are all either true or false They all compare numbers They all check whether something is true or not

2<5 (2 is less than 5) What is the answer? True or False Question – what is the answer? True When students answer go to the next slide

True or False 2<5 (2 is less than 5) “2<5” is called a Boolean expression. Boolean expressions help computers make decisions. Question – what is this? It is a Boolean expression Background for the Teacher - Boolean expressions are derived from Boolean logic which is a form of Algebra that reduces all values either TRUE or FALSE. Boolean logic is named after the nineteenth century mathematician George Boole. Computers and robots make decisions based on Boolean logic. A Boolean expression is a three-part clause that consists of two items to be compared, separated by a comparison operator.  For example, 5>3 (5 is greater than 3) is a Boolean expression and the result of that expression is TRUE. Boolean expressions compare values using relational operators. Relational operators compare the two values and the result is either TRUE or FALSE. Teacher note – ask if this is true or false

What are the parts of a Boolean expression? Boolean Expressions 2<5 What are the parts of a Boolean expression? Review the parts of a Boolean expression A Boolean expression is a three-part clause that consists of two items to be compared, separated by a comparison operator.  Boolean expressions compare values using relational operators. Relational operators compare the two values and the result is either TRUE or FALSE. Teacher note – ask if this is true or false

Common Relational Operators 2<5 The“<“ sign compares two numbers and is called a relational operator. Common Relational Operators equal to not equal to greater than less than greater than or equal to less than or equal to == != >  <  >= <= Introduce the concept of a relational operator Relational operators compare the two values and the result is either TRUE or FALSE.

Review of Boolean expressions 5<3 is this expression true or false A Boolean expression is a three-part clause that compares two values that are separated by a relational operator and results in a value that is TRUE or FALSE. Which are the two values? Which is the relational operator? Background for the Teacher - Boolean expressions are derived from Boolean logic which is a form of Algebra that reduces all values either TRUE or FALSE. Boolean logic is named after the nineteenth century mathematician George Boole. Computers and robots make decisions based on Boolean logic. A Boolean expression is a three-part clause that consists of two items to be compared, separated by a comparison operator.  For example, 5>3 (5 is greater than 3) is a Boolean expression and the result of that expression is TRUE. Boolean expressions compare values using relational operators. Relational operators compare the two values and the result is either TRUE or FALSE

How do robots make decisions? 540 mm Look at each statement below and decide if it is TRUE or FALSE. “The robot is more than 400mm from the wall” Distance from wall > 500mm Distance from wall == 500mm 400mm > Distance from wall “The robot is 540mm long” Distance from wall == 540mm “The robot is not 540mm from the wall” Distance from wall < 1000mm Which of these statements are true and which are false? Which are Boolean expressions and which ones are not?