Four-Bar Walker
Linkages turn one spinning motor into legs that walk a robot forward without wheels.
Start building ↓The build
Build the legs
Make four-bar linkages that swing in a walking arc.
Couple to motor
Drive both sides from one motor with offset cranks.
Phase the legs
Set legs so they alternate like real steps.
Walk
Power on and it strides forward.
A four-bar linkage turns continuous rotation into a foot path that pushes back on the ground, stepping the robot forward.
A closer look
Mechanical linkages can encode complex gaits from a single input, the principle behind classic walking toys and theme-park robots.
Variables to test
- 1 Change the crank offset — how does the gait change?
- 2 Add a tail for stability — fewer tumbles?
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