Competition robotics challenges students to design, build, program, and drive robots that complete game tasks under time limits. FRC, VEX, and FLL each use different robot sizes, tools, and rules, but they all reward teamwork, engineering design, and clear problem solving. This cheat sheet helps students organize the major ideas needed before, during, and after a robotics season.
It is useful for quick review in the shop, classroom, pit, or competition venue.
The most important skills are understanding the game, choosing a simple strategy, building reliable mechanisms, writing tested code, and documenting decisions. Strong teams use an engineering design cycle: define the problem, brainstorm, prototype, test, improve, and communicate. Match success often depends on consistency more than complexity.
A robot that performs one or two important tasks reliably is usually better than a robot that attempts many tasks poorly.
Key Facts
- The engineering design cycle is: identify the problem, brainstorm solutions, prototype, test, improve, and share results.
- A good robot strategy starts with scoring value per time, calculated as points per cycle = points scored in one trip or action divided by time for that cycle.
- Reliability matters because expected match contribution = average points scored x success rate.
- For drivetrains, speed and pushing force trade off because higher gear ratios usually increase torque while lower gear ratios usually increase speed.
- In autonomous programming, sensors improve accuracy by giving feedback such as distance, angle, color, line position, or object detection.
- A simple PID idea is error = target value - measured value, and the robot adjusts motor output to reduce that error.
- Before competition, every robot should pass a checklist for battery charge, loose wires, legal size, legal parts, firmware, code version, and safety inspection.
- Strong drive team communication uses short role-based calls such as driver, operator, coach, human player, and technician.
Vocabulary
- FRC
- FIRST Robotics Competition is a high school robotics program using large custom robots, yearly games, alliances, and an intense build and competition season.
- VEX
- VEX Robotics is a competition system where teams build medium-sized robots from reusable parts to complete yearly game challenges.
- FLL
- FIRST LEGO League is a robotics program where students use LEGO-based robots, coding, research, and teamwork to solve themed challenges.
- Autonomous
- Autonomous means the robot acts from prewritten code without direct driver control for part or all of a match.
- Drivetrain
- The drivetrain is the system of motors, wheels, gears, belts, chains, or tracks that moves the robot around the field.
- Prototype
- A prototype is a quick test version of a mechanism or idea built to learn whether it works before making the final design.
Common Mistakes to Avoid
- Trying to do every game task, which is wrong because a complicated robot often becomes unreliable and hard to finish before competition.
- Ignoring the rulebook, which is wrong because illegal dimensions, parts, mechanisms, or match actions can fail inspection or earn penalties.
- Testing only when the robot is finished, which is wrong because early testing finds design, wiring, and programming problems while they are still easy to fix.
- Changing code or hardware at competition without recording it, which is wrong because the team may not know what caused a new problem or how to undo it.
- Designing without drivers and pit crew in mind, which is wrong because a robot must be easy to control, repair, carry, charge, and inspect under time pressure.
Practice Questions
- 1 A robot scores 12 points in a 20-second cycle. What is its points per second, and how many points would it average in 100 seconds at that same rate?
- 2 A mechanism succeeds 8 times out of 10 and scores 15 points each time it works. What is its expected point value per attempt?
- 3 During testing, an autonomous routine drives 60 cm when the target is 75 cm. What is the distance error using error = target value - measured value?
- 4 A team can build either a simple robot that scores one task very reliably or a complex robot that attempts three tasks but often breaks. Explain which choice is usually stronger for competition and why.
Understanding Competition Robotics Guide (FRC, VEX, FLL)
The rules manual is an engineering document, not just a list of penalties. Read it with a notebook and turn each scoring rule into a design requirement. Record field dimensions, starting locations, protected zones, match periods, robot limits, and ways points can be lost.
A high-value action may be a poor choice if it requires a long trip across the field or careful alignment under defense. Teams should build a simple field map before designing mechanisms. Even a tape outline on a classroom floor can reveal turning space, sight lines, traffic jams, and places where a robot may get stuck.
Robot design works best when each system has a clear job. The drivetrain moves and turns. The intake collects game pieces.
The launcher, lift, arm, or gripper places them. Power flows from the battery through legal protection devices, wiring, motor controllers, and motors. A weak link in this chain can stop an otherwise excellent robot.
Motors draw more current when stalled, which can heat wires and trip breakers. Gears, chains, belts, shafts, and bearings must be aligned so they waste little energy through rubbing.
Students should learn to notice unusual sounds, hot motors, loose fasteners, and bent parts. These small signs often predict failure before a match.
Programming becomes more dependable when code is divided into small behaviors that can be tested alone. One behavior might drive forward a set distance. Another might raise an arm to a safe height.
A third might detect a game piece. Sensors are useful only after they are calibrated and checked against real conditions. Wheel encoders can be affected by slipping.
Gyros can drift or be disturbed by collisions. Cameras need stable lighting and a clear view. Autonomous routines should include time limits and safe fallback actions.
If a sensor reading is missing, the robot should avoid repeating a dangerous command forever. In driver control, use limits that prevent mechanisms from moving into the frame, floor, or another mechanism.
Testing needs numbers, not only opinions. Time repeated cycles and write down both the fastest result and the usual result. Run mechanisms with a full battery, then with a battery at a lower normal voltage.
Test after the robot has been carried, bumped, or driven hard, since vibration exposes wiring faults. Keep a change log that states what changed, why it changed, and what happened afterward. At events, the pit crew should make only deliberate repairs and record them.
The drive team should practice a routine for match setup, autonomous selection, communication, and post-match inspection. Calm, specific calls reduce confusion when the field is loud and the match clock is moving quickly.