Hexapod · Field Manual

GOAL: TRIPOD GAIT VERIFIED IN-AIR, THEN ONE WEIGHT-BEARING STEP ON THE FLOOR. · 2 EVENINGS · DAY 9–10

01 · Safety prerequisites

▸First power-on: no servos plugged in

Boot ESP32 + PCA9685s only. Verify 0x40 and 0x41 over serial. Then plug in one servo at a time.

▲Tie ESP32 GND to servo-rail GND

Separate grounds cause random PWM glitches. This has confused many people. Tie them at the buck GND.

02 · What you need from Shop

03 · Tasks

T17Body class — IK-based neutral stance· depends T11, T16

Acceptance:Stable, symmetric stance; weight evenly distributed; commanded via Body.stand() through IK.

T18Tripod gait — in-air verification· depends T17

Acceptance:Correct tripod alternation observed mid-air: legs 0/2/4 sweep together, then 1/3/5; no leg jams or fights another.

T19First weight-bearing step· depends T18

Acceptance:Robot advances ≥ 100 mm without falling, on a non-slippery surface, within 2 tuning iterations.

Calibration steps

STEP 1
Always in-air before on-the-ground
First power-up of any new gait is with the robot suspended (a stand or someone holding the body). Tibia rotation under load is what strips MG996R gears. Bench-first, always.
STEP 2
Start on a rug or rubber mat
Polished tile and hardwood are slip traps for foot pads. A rug or rubber mat for the first walk tells you whether the gait works without confusing it with floor traction.

Reference docs

Phase 4 — First steps.