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Glossary

Technical terms explained simply for 8th graders.


A

Alliance

Two teams that work together during a match. In VEX competitions, you're paired with a different alliance partner for each match.

Arcade Drive

A control scheme where one joystick controls both forward/backward movement AND turning. The robot mixes these inputs to calculate motor speeds.

Autonomous

The 15-second period at the start of each match where robots run pre-programmed code with NO driver input. The robot drives itself!

Axis

A joystick direction. VEX controllers have 4 axes: - Axis 1: Right stick left/right - Axis 2: Right stick up/down - Axis 3: Left stick up/down - Axis 4: Left stick left/right


B

Boolean

A data type that can only be True or False. Used for yes/no decisions in code.

Brain

The VEX V5 Brain - the main computer that runs your robot's code. Has a touchscreen, 21 ports, and a battery connector.

BRAKE

A motor stopping mode where the motor actively resists movement. The robot stops quickly but can still be pushed.


C

Calibrate

To set a sensor's starting reference point. For example, the inertial sensor needs 3 seconds to calibrate before use.

Cartridge

The colored gear insert inside a VEX V5 motor that determines its speed/torque ratio: - Blue (6:1): 600 RPM, low torque - Green (18:1): 200 RPM, medium torque - Red (36:1): 100 RPM, high torque

Center of Gravity

The point where a robot's weight is balanced. If this is too high or off-center, the robot may tip over.

COAST

A motor stopping mode where the motor stops applying power but doesn't resist movement. The robot coasts to a stop gradually.

Controller

The handheld device drivers use to control the robot during the driver control period.


D

Deadband

A zone around joystick center (usually 5-10%) where small movements are ignored. Prevents drift when the joystick isn't perfectly centered.

Degrees

A unit of rotation. A full circle is 360 degrees. Used for motor positions and turns.

Derivative (D)

In PID control, the term that predicts future error based on how fast the error is changing. Helps prevent overshoot.

Descoring

Removing blocks that your opponent has scored. In Push Back, this is legal and can be a key strategy!

Driver Control

The 1 minute 45 second period after autonomous where drivers control their robots using controllers.

Drivetrain

The motors and wheels that move your robot. A 4-motor tank drive uses 4 motors connected to 4 wheels.


E

Error

In PID control, the difference between where you want to be (target) and where you are (current). Error = Target - Current.


F

Float

A data type for decimal numbers like 3.14 or -0.5. Used for precise calculations.

Force

A push or pull on an object. Measured in Newtons (N). More force = more acceleration (F = m × a).

Forward

The direction the front of the robot faces. In code: FORWARD constant.

Friction

The force that resists motion between surfaces. More friction = more traction but harder to slide.

Function

A reusable block of code that performs a specific task. Like a recipe you can use over and over.


G

Gear Ratio

The relationship between two connected gears. A 2:1 ratio means the output gear turns once for every 2 turns of the input gear.

GPS Sensor

A VEX sensor that knows the robot's exact position on the field. Uses a special stripe code on the field perimeter.


H

Heading

The direction the robot is facing, measured in degrees (0-360). North = 0°, East = 90°, etc.

HOLD

A motor stopping mode where the motor actively maintains its position. The robot stops and resists being pushed.


I

Inertial Sensor (IMU)

A sensor that measures the robot's rotation and tilt. Essential for accurate autonomous turns.

Integer (int)

A data type for whole numbers like 1, 42, or -7. No decimal points.

Integral (I)

In PID control, the term that accumulates error over time. Helps reach the target when P alone isn't enough.


J

Joystick

The movable sticks on the controller. Each joystick can move in two directions (X and Y), giving 4 total axes.


K

Kp, Ki, Kd

The tuning constants for PID control: - Kp: Proportional gain (how aggressively to correct) - Ki: Integral gain (how fast to accumulate error) - Kd: Derivative gain (how much to dampen changes)


L

Loop

Code that repeats. A while True: loop runs forever. A for loop runs a specific number of times.


M

Millimeters (MM)

A unit of distance. 1000 mm = 1 meter. About the width of a fingernail.

Momentum

Mass times velocity. A heavier or faster robot has more momentum and is harder to stop.

Motor

A device that converts electrical energy into rotational motion. VEX V5 Smart Motors have built-in sensors for position and speed.

Motor Group

Multiple motors controlled together as one unit. Used for left-side and right-side drive motors.


N

Newton

The unit of force. Named after Isaac Newton. 1 Newton is about the weight of a small apple.


O

Omni Wheel

A wheel with small rollers around its edge that allow sideways sliding. Great for turning but provides less pushing power.

Optical Sensor

A VEX sensor that detects colors and proximity. Useful for sorting blocks by alliance color.

Overshoot

When the robot goes past its target, then has to correct back. Happens when corrections are too aggressive.


P

Parameter

A value you pass into a function. Like ingredients in a recipe.

Parking

Positioning your robot in a designated zone at the end of a match for bonus points.

PERCENT

A unit for motor speed. 100% = maximum speed, 50% = half speed.

PID Control

A control algorithm (Proportional-Integral-Derivative) that makes robot movements more accurate and smooth.

Port

A numbered connection point on the V5 Brain (1-21) where you plug in motors and sensors.

Proportional (P)

In PID control, the term that corrects based on current error. Bigger error = bigger correction.

Push Back

The VEX IQ 2025-2026 competition game. Teams push blocks into goals and control zones to score points.


Q

(No terms)


R

Reverse

The opposite of forward. In code: REVERSE constant.

Reversed Motor

A motor where positive velocity spins it backward. Right-side motors are typically reversed because they're mounted as a mirror of the left side.

RPM

Revolutions Per Minute - how many times a motor shaft completes a full rotation in one minute.

RSID

In programming, a unique identifier. In VEX code, helps track different parts of the document.


S

Sensor

A device that measures something in the environment (distance, color, rotation, position).

Skills

A competition format where one robot runs solo for 60 seconds instead of playing with an alliance.

Spin

To make a motor rotate continuously. motor.spin(FORWARD) keeps the motor running.

State Machine

A programming pattern where code tracks which "state" it's in and behaves differently in each state.

String (str)

A data type for text, like "Hello!" or "Red Team". Always in quotes.


T

Tank Drive

A control scheme where each joystick controls one side of the robot. Left stick = left motors, right stick = right motors.

Timeout

A safety limit that stops an action if it takes too long. Prevents your robot from getting stuck.

Torque

Rotational force. Higher torque = more pushing power but lower speed.

Traction

How well wheels grip the surface. More traction = better pushing, less slipping.

Turn

Rotation around the robot's center. turn_for(RIGHT, 90, DEGREES) rotates 90° clockwise.


U

(No terms)


V

Variable

A named container that stores a value. Like a labeled box holding something.

Velocity

Speed in a specific direction. Can be positive (forward) or negative (reverse).

VEX V5

The current VEX IQ robotics platform with V5 Brain, Smart Motors, and various sensors.


W

Wait

A command that pauses code execution. wait(1, SECONDS) pauses for 1 second.

Wheel Travel

The distance a robot moves in one full wheel rotation. Equals wheel circumference (π × diameter).

While Loop

A loop that runs as long as a condition is true. while True: runs forever.


X, Y, Z

X-Axis

Horizontal direction (left/right). On joysticks: Axis 1 and Axis 4.

Y-Axis

Vertical direction (up/down). On joysticks: Axis 2 and Axis 3.

Zone Control

In Push Back, having the most blocks of your color in a zone to earn bonus points (6-10 points per zone).


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