Lesson 5 · Build Motor Claw and Add Pinchers

Suggested Time: 30-60 minutes

Lesson Plan


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Lesson Overview

In this lesson we will assemble the claw and add pinchers.

Tutorial Video


STEP 1. Build Claw Motor Assembly

Build claw motor assembly using:

  • 1 x Servo Motor
  • 4 x Wood Pieces
  • 4 x M3x10 Screws

Side 1 Side 2

STEP 2. Attach Pinchers

Build left pincher assembly using:

  • 1 x M3x10 Screw
  • 3 x Wood Pieces

This pincher will be driven by the claw drive gear.

IMPORTANT: Do not overtighten. Make sure that the joint can move easily. If it is too tight, your motors will not be able to move the joint during robot arm operation.

Attach left pincher using:

  • 1 x M3x12 Screw
  • 1 x Wood piece

You’ll need to be careful to slide the wood piece in between the left pincher assembly like meat in a sandwich and then align the holes so that the screw can go through all of the pieces.

Top View Bottom View

Attach right pincher using:

  • 1 x M3x10 Screw
  • 1 x Wood Piece

When inserting the right pincher, align the gears so that the claw can open and close all the way.

IMPORTANT: Don’t tighten the screw all the way. Be careful to make sure that the screw does not protrude past the wood surface (see below in the red circle) If it does, the claw will get stuck when the drive motor tries to move it.

Top View Make sure screw does not protrude!

Additional Resources