Learning Portal

Our hands-on, comprehensive lesson plans span a range of levels. Browse our free STEM and coding learning resources.

Marty Image

3.01: Secret Handshake

45 Minutes

Lesson Overview

We have already looked at responding to obstacles using IR sensors, but another way to respond to the environment is to look at the position readings from the servo motors. Doing this, we can tell when pressure is placed on Marty’s arm, causing a small change in it's position and program him to respond, for example, to carry out a handshake with someone!

Key vocabulary:
    Servo , Motor reading , Pressure , Reaction/Response , Force,

Content Sections

  • Learning Objectives
    1. Extensions & Challenges
      • Additional Reading
      • 3.01: Secret Handshake

        45 Minutes

        Lesson Overview

        We have already looked at responding to obstacles using IR sensors, but another way to respond to the environment is to look at the position readings from the servo motors. Doing this, we can tell when pressure is placed on Marty’s arm, causing a small change in it's position and program him to respond, for example, to carry out a handshake with someone!

        Key vocabulary:
          Servo , Motor reading , Pressure , Reaction/Response , Force,
        • An understanding of the sensing blocks and conditional statements
        • Tablet with Bluetooth 4.2+
          • Marty the Robot
          • Marty Workbook
          • Tablet with Bluetooth 4.2+
          • Access to the MartyBlocks editor

        Learning Objectives

        • Explore the position values that are being read from the servo motors during different movements/pressures
        • Understand that when pressure is placed on an arm the position recorded by the servo motor will change as the arm joint rotates
        • Program Marty to carry out a handshake when someone puts pressure on Marty’s arm
        • We have already programmed Marty to respond to touch using IR sensors but another way we can do respond to the environment this is by reading the position values of the servo motors
        • In small groups, get students to create variables that hold the motor position value for Marty’s left and right arms. Note down what the values are when his arms are positioned straight out in front of him, straight behind him and down by his side
        • Explore the maximum and minimum values the servo motor position values can take. Are they what you would expect?
          • Note: the servo motor position sensors don't have a full 360 degree range. Thus the maximum and minimum values are approximately -145 degrees and +145 degrees, smaller than you would expect for a full 360 degree range
        • Program Marty to take part in a short handshake with someone when a small force is applied to his arm causing it to change position by a small amount
        • Extend the handshake to create a unique and secret handshake between your group and Marty

        Extensions & Support

        • Explore what the values are for the other joints with motors (the dropdown list will help if students aren’t sure which joints will have a motor reading associated!)
        • Program Marty to respond to a movement of these different joints – for example, on the eyes!

        Additional Reading

        • Educator’s Guide
        • Introduction to Programming with MartyBlocks

        • Middle School Technology Applications: Grade 6 to Grade 8
        • Technologies: Computing Science
        • Literacy & English: Listening and Talking
        • Health and Wellbeing: Mental, Emotional, Social and Physical Wellbeing
        • Literacy & English: Writing
        • Computing, Design and Technology: Design and Technology
        • Computing, Design and Technology: Computing
        • CSTA Education Standards
        • Digital Technologies, Design & technologies: Design & Technologies
        • Digital Technologies, Design & technologies: Digital Technologies
        • International Society for Technology in Education (ISTE)