Introduction

What are Control Systems?

A control system is how your robot responds to commands and adjusts its behavior based on what's happening around it. Think of it like this: when you drive a car, you don't just turn the steering wheel once and hope for the best — you constantly make small adjustments based on where the car is going. Your robot needs to do the same thing!

In FTC robotics, control systems handle everything from simple tasks like "move forward when I push the joystick" to complex operations like "keep the arm at exactly 45 degrees no matter what."

Why Control Systems Matter

Without good control, even the best-built robot will:

• Overshoot targets and miss game pieces
• Drift off course during autonomous
• Respond unpredictably to driver inputs
• Waste time with imprecise movements

With proper control systems, your robot becomes:

• Precise — Goes exactly where you want it
• Responsive — Reacts quickly to commands
• Stable — Maintains position even under load
• Predictable — Behaves consistently every time

Core Concepts

Open-Loop Control

This is the simplest type of control: you give a command, the robot executes it, and that's it. No feedback, no adjustments.

Example: Setting a motor to 50% power and hoping it moves the arm to the right position.

Pros:

• Simple to program
• Fast execution
• Works fine for simple tasks

Cons:

• No way to know if it worked
• Affected by battery level, friction, weight
• Inconsistent results

Closed-Loop Control (Feedback Control)

This is smarter control: you give a command, the robot checks if it's doing the right thing, and adjusts automatically.

Example: Telling the robot "go to 45 degrees," and it constantly checks its angle and corrects itself until it reaches exactly 45 degrees.

Pros:

• Self-correcting
• Consistent results
• Handles disturbances (like game pieces changing weight)

Cons:

• More complex to program
• Requires sensors
• Needs tuning to work properly

What You'll Learn

In this section, we'll cover:

• Manual Control — How to map gamepad inputs to robot actions
• Motor Commands — Different ways to control motors and when to use each
• PID Control — The most important feedback algorithm in FTC
• Motion Profiling — Smooth, controlled movements instead of jerky stops and starts
• Practical Examples — Real code you can use on your robot

Getting Started

Start with manual control to understand the basics, then move on to PID control once you're comfortable with sensors and feedback loops. Don't worry if PID seems complicated at first — we'll break it down step by step!