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Navigation · Sampling-Based and Kinodynamic Planning · M4-L4 · Advanced

Park the Car-Like Robot

Incident report · Meridian General Hospital

19:45. The new tug that carries oxygen cylinders cannot turn on the spot: its tightest turn has a radius of 1.2 m. A route planned for Scout makes it stop, back up, stop and back up again in front of the charging bay.

You will build the exact curves such a vehicle can drive, pick the shortest, and then plan the last metres so that the tug backs into the bay in one move.

Your task

    Simulation
    solution.pyLoading Python…
    Ctrl+Enter runs
    What Python can I use?

    Plain Python with math and heapq. Your code runs in a background worker: an endless loop is stopped after a few seconds and the page stays usable. It runs in your browser and is never sent anywhere.

    Hints

    What this lab teaches

    Stage 1 is the outer-tangent circle-line-circle path, including the angle wrapping that keeps every arc forward. Stage 2 adds the inner tangents and picks the shortest of four words. Stage 3 plans a path with a gear change: forward to a staging pose, then straight back into the bay.

    Grading drives your path from the start pose with exact arc and line formulas and compares where it ends, whether it ever reverses, and its length.

    Theory for this lab

    Sampling-Based and Kinodynamic Planning labs

    1. M4-L1: Collision-Check a Footprint
    2. M4-L2: Grow an RRT
    3. M4-L3: Rewire to a Better Path with RRT*
    4. M4-L4: Park the Car-Like Robot: this lab.

    Educational simplification: no obstacles, so the lab is about the shape of the curves; goals farther than four turning radii from the start, where circle-line-circle is always shortest; one gear change in the last stage instead of the full Reeds-Shepp search.

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