Walking Robot
One motor spins in a circle. Your team turns that circle into footsteps. Design a walking robot with 2 to 6 legs, all driven by a single TT motor, and make it cover as much ground as it can in 15 seconds.
The target
One hook, one number: how far your robot walks in 15 seconds.
Farthest distance walked in 15 seconds.
Benchmark: 90 cm.
best distance in 15 s vs. 90 cm
5 = reaches the benchmark. 3 = walks the full 15 seconds but falls short. 1 = stalls, tips over, or barely moves. Full wording is on How It's Scored.
How the run works
- Start behind the line. Set the robot down with every foot behind the start line.
- Flip the switch. The clock starts when the switch goes on. No pushing, no steering, no touching.
- 15 seconds. When time is up, the robot stops where it is.
- Measured straight ahead. Distance is measured from the start line to the robot's rearmost foot, straight forward, not along the path it walked. A robot that curves loses distance.
- Best of 3 runs. Your best run counts.
The rules
- 2 to 6 legs. Only feet touch the floor. No wheels or rollers, and nothing built to slide.
- One motor: the blue biaxial TT motor with metal gears. It has a shaft out both sides. Every leg runs off this one motor.
- Four 1.2 V AA rechargeable batteries. That's 4.8 V total. No other power.
- An on/off switch between the batteries and the motor. Required.
- Links: about 1/8 in thick wood panels.
- Joints: spacers or standoffs, either threaded or with a bolt through them.
- Gears: laser cut or 3D printed. You'll probably need them to carry the motor's turn to every leg.
- Shoes: rubber bands, hot glue, or anything else that adds grip to the feet.
- Size: fits inside 30 × 30 × 30 cm.
What you hand in
Everything below goes into one Google Slides deck, attached to the Google Classroom assignment. Take pictures of each part as you go — notebook pages, screenshots, and builds — and add them to the deck. That deck is your build log, and it's what your team shows at the gallery walk.
- Research and brainstorms. Photos of your notebook pages: walkers you looked at, and several leg ideas sketched by hand.
- Your linkage in the MIT Linkage Designer. Screenshots of the leg you picked, with its foot path and the DOF readout showing.
- Your computations. Photos of the notebook pages where you worked out each check by hand. See the box below.
- Your Onshape model. Screenshots of the links, gears, and chassis, assembled with mates.
- Prototype versions and change tracking. A photo of every version, and what failed, why, and what you changed. See change tracking.
- The final build. Photos of the finished robot from the side and from above, and your best 15-second distance.
- The robot itself. Walking, switched, and within every rule above.
- The gallery walk. No formal presentation. Your robot and the deck sit at a station. Classmates come by, try the robot, and you walk them through it. Part of the time you're the one visiting other stations. See how it works.
Your notebook and your deck must show these three computations for the leg you build. Write out every step, not just the answer.
- Degrees of freedom: count n and j₁ (include ground, watch shared pins) and show M = 3(n − 1) − 2j₁ − j₂ = 1.
- Grashof compliance: list the four lengths of every loop that contains the crank, and show s + l < p + q.
- Transmission angle: work out μ with the crank at 0° and at 180°, and show both stay between 40° and 140°.
Dates
Where to start
- MIT Linkage Designer: the simulator from class. Build a leg, mark the crank as the motor and the foot as the target, and watch the path it draws.
- Strandbeest: Theo Jansen's walking machines. The Jansen leg on the guidance page comes from his published link lengths.
- Design Lab: type in your link lengths and check Grashof, transmission angle, the foot path, and whether one motor can drive it. Then predict your distance.
- The design checks: run every one before you cut a single part.
Before you cut or print anything, read Making Parts in the shop procedures. Wasted wood and filament count on your daily grading page score.
