SOLID STATE PRESS
← Back to catalog
Robotics: How Machines Move and Sense cover
Coming soon
Coming soon to Amazon
This title is in our publishing queue.
Browse available titles
Artificial Intelligence

Robotics: How Machines Move and Sense

Actuators, Sensors, and the Sense-Plan-Act Loop — A TLDR Primer

Robotics class or a first AI course just introduced sense-plan-act loops, PID control, and inverse kinematics — and the textbook buries the actual ideas under pages of dense notation. This TLDR primer is built for the student who wants to understand how a robot actually works before the exam, not after.

It walks through the full picture in plain language: how sensors turn raw signals into usable data, how motors and gears turn spin into motion, how a robot arm figures out where its hand is (forward kinematics) and where to put it (inverse kinematics), and how feedback control keeps a system from overshooting its target. Concrete 2D examples replace abstract derivations, and every term is defined the moment it shows up — no assumed background in circuits or calculus.

This is an intro to robotics study guide for high schoolers and early college students who need to walk into a test, a robotics club meeting, or a first AI course already oriented. It's also useful for parents and tutors who need to get up to speed fast enough to help. The sense-plan-act loop explained here is the same framework used in real robotics courses, just stripped to essentials — no filler, no padding, no chapters you'll skim past.

By the end you'll know the difference between open-loop and closed-loop control, why a robot needs both proprioceptive and exteroceptive sensors, and how modern learning-based robots build on these same fundamentals. Concise, concrete, and to the point.

Grab it, read it, and go into class already knowing how the pieces fit together.

What you'll learn
  • Describe the sense-plan-act loop and identify each stage in a real robot
  • Explain how common sensors (encoders, IMUs, cameras, LIDAR, ultrasonic) convert physical signals into data
  • Distinguish DC motors, servos, and stepper motors and pick the right actuator for a task
  • Use basic forward kinematics and degrees of freedom to reason about robot arms
  • Understand feedback control, especially the intuition behind PID
  • Recognize how modern robots fuse sensing, control, and AI to navigate the real world
What's inside
  1. 1. What a Robot Actually Is
    Defines a robot as a sense-plan-act system and introduces the three-part loop that structures the rest of the book.
  2. 2. Sensing: How Robots Perceive the World
    Covers the main sensor families — proprioceptive and exteroceptive — and how raw signals become usable data.
  3. 3. Moving: Actuators and Mechanisms
    Explains DC motors, servos, and steppers, plus how gears and linkages convert motor spin into useful motion.
  4. 4. Kinematics: Getting from Joints to Position
    Introduces forward and inverse kinematics for robot arms and mobile robots using simple 2D examples.
  5. 5. Control: Closing the Loop with Feedback
    Explains open-loop vs closed-loop control and builds intuition for PID through concrete examples.
  6. 6. Putting It Together: Autonomy, AI, and Where Robotics Is Going
    Shows how sensing, control, and modern AI combine in navigation, manipulation, and learning-based robots.
Published by Solid State Press
Robotics: How Machines Move and Sense cover
TLDR STUDY GUIDES

Robotics: How Machines Move and Sense

Actuators, Sensors, and the Sense-Plan-Act Loop — A TLDR Primer
Solid State Press

Robotics: How Machines Move and Sense

Actuators, Sensors, and the Sense-Plan-Act Loop — A TLDR Primer

Copyright © 2026 Solid State Press.

Published by Solid State Press.

All rights reserved. No part of this book may be reproduced or transmitted in any form without prior written permission, except for brief quotations in critical reviews and educational use.

Part of the TLDR Study Guides series.

Contents

  1. 1 What a Robot Actually Is
  2. 2 Sensing: How Robots Perceive the World
  3. 3 Moving: Actuators and Mechanisms
  4. 4 Kinematics: Getting from Joints to Position
  5. 5 Control: Closing the Loop with Feedback
  6. 6 Putting It Together: Autonomy, AI, and Where Robotics Is Going
Chapter 1

What a Robot Actually Is

A robot is a physical machine that senses its environment, decides what to do, and then acts on the world to change it. That three-step cycle — sense, plan, act — is the single idea this entire book unpacks. Every robot you can think of, from a Roomba bumping around a living room to a factory arm welding car doors, runs some version of this loop over and over, many times per second.

Start with the vacuum. Its bump sensor or infrared distance sensor tells it a wall is close (sense). Its internal logic decides to turn 90 degrees (plan). Its wheel motors spin to carry out that turn (act). Then the loop repeats: sense again, plan again, act again. Strip away the plastic shell and the marketing, and that's the whole machine.

This loop is why robotics sits at the intersection of several fields at once. Sensing is about signal processing and electronics — turning light, sound, or motion into numbers a computer can use (covered in the next section). Acting is about motors and mechanisms — turning electrical current into physical force and motion (Section 3). Planning is about software: control algorithms, math, and increasingly, artificial intelligence (Sections 5 and 6). A robotics engineer has to think across all three, because a failure anywhere in the loop breaks the whole system. A perfect motor is useless if the sensor feeding it bad data tells it to drive off a table.

A concept tightly bound to this loop is embodiment — the idea that a robot doesn't just compute, it exists as a physical object with mass, friction, and momentum that push back against it. This is what separates robotics from ordinary software. A chess program that "decides" a bad move can just take it back. A robot arm that decides on a bad move has already knocked over the glass. Embodiment means every plan has to account for physics: how long a motor takes to spin up, how much a wheel slips on tile, how a joint sags under load. You'll see this idea resurface constantly — it's why control (Section 5) exists as its own discipline instead of being an afterthought.

About This Book

If you're a high school student in a robotics club or an intro engineering elective, a college freshman tackling your first robotics or mechatronics course, or a parent trying to make sense of your kid's FIRST Robotics project, this book is for you. It also works as a quick refresher before a robotics competition or a lab practical where you need robotics basics for beginners explained fast, not buried in a 400-page textbook.

This is an intro to robotics study guide covering how do robots sense and move, walking through a robot sensors and actuators guide, kinematics for beginners explained step by step, PID control explained simply, and the sense plan act loop explained in plain language — the cycle every robot uses to perceive, decide, and act. A concise overview with no filler, built to get you oriented fast.

Read it straight through first, then work through the examples as you go. A short problem set at the end lets you check whether the ideas actually stuck before your test, project, or competition.

Keep reading

You've read the first half of Chapter 1. The complete book covers 6 chapters — readable in one sitting.

Coming soon to Amazon