Robotics 1.0 Lesson Plan
Lesson 22: Assemble the Claw

Purpose: Assemble a two-joint robotic arm with a gripper using servo motors.

No. of. Classes

1 - (Time : 1:30 minutes, Each group maximum 4 children).

Materials Required

Laptop or desktop with Mu Editor installed.

CircuitPython installed on CPX board.

Circuit express board (CPX), Crickit, 5v Battery, USB cable.

3 MG995 Servos - two Continuous servos and one 180 servo.

Servo Bracket and U bracket set

Cligo gripper kit

Jumper wires.

Curriculum Content 6.3 Joystick Module
7.1 Servo Motors
7.5.3 Motion Types - Gripper
7.5.4 Motion Types - 2DOF Arm
8.1 Identifying Problems to Automate
Prior knowledge

  • Connect and power servo motors using the CPX and Crickit
  • Understand the difference between continuous rotation servos and 180 degree servos
  • Familiarity with basic mechanical assembly using brackets
  • Upload and run CircuitPython code using the Mu Editor

    • Exercises

    Exercise:1


  • Use this video and this instruction document to assemble the arm and the gripper


    • Teacher's Instruction
    1. Explain the goal of building a two joint robotic arm with a working gripper.
    2. Introduce the different servo motors and explain the difference between continuous rotation servos and 180 degree position servos.
    3. Show how the servo brackets, U brackets, and gripper parts fit together to form the arm structure.
    4. Demonstrate how to mount each servo so that it controls a specific joint of the arm.
    5. Explain how external 5V power is required to safely run multiple MG995 servos.
    6. Guide students to follow the assembly video and instruction document step by step.
    7. Check that all screws, brackets, and servo horns are tightly fixed before powering the system.
    8. Discuss how real robotic arms use joints and grippers to pick and place objects.
    9. How many joints are there in this Robotic Arm? How does adding more joints to a robotic arm change what it can reach and pick up?