Objective: In this activity, you will add gears to your mobile robot to have it move at a precise speed.

Design Specifications •Your robot must move at a speed between 8.5 cm/sec and 9.5 cm/sec. •You may use any combination of gears and any wheel size that you want.

What You Should Know Bevel Gear Compound Gear Ratios Gears Gears and Speed

Idler Gear Lego Gear Combinations Programming: Motors Spur Gear

Helpful Hints • As a first step, design a mobile robot with gears and measure its speed. Determine if it needs to go faster or slower. Determine how much faster or slower? Redesign the gearbox with the right ratios. • Use the RCX's internal clock to run the robot for a precise amount of time. That way, you won't need a stopwatch.