| name | backward-roll |
| description | Performs a backward roll on the ground and comes back up, via a low sequence that drops root.y and sweeps root.faceDeg backward. Use when a command mentions backward roll, back roll, roll backwards, or roll over backward and up. |
| category | locomotion |
| disable-model-invocation | true |
| subskills | ["move-torso","move-leg","balance-and-posture"] |
backward-roll
Sit back low, tuck, roll backward (a backward faceDeg sweep while down), and recover to a stand.
Composes: move-torso + move-leg + balance-and-posture
How
- Use a
sequence with loop:false. Sit/drop (root.y-0.5, legs tucked), roll back (root.y-0.75, faceDeg 0 → -180 → -360), rise to rest.
durationMs ~1600.
Example
- "do a backward roll" ->
{"durationMs":1600,"say":"Backward roll!","sequence":{"loop":false,"frames":[{"t":0,"pose":{"LeftUpLeg":[90,0,0],"LeftLeg":[110,0,0],"RightUpLeg":[90,0,0],"RightLeg":[110,0,0],"Spine":[30,0,0]},"root":{"y":-0.5,"z":-0.2}},{"t":0.5,"pose":{"LeftUpLeg":[120,0,0],"RightUpLeg":[120,0,0],"Spine":[20,0,0]},"root":{"y":-0.75,"z":-0.5,"faceDeg":-180}},{"t":1,"pose":{"LeftUpLeg":[0,0,180],"LeftLeg":[0,0,0],"RightUpLeg":[0,0,180],"RightLeg":[0,0,0],"Spine":[0,0,0]},"root":{"y":0,"z":-0.6,"faceDeg":-360}}]}}
Limits & posture
Keep ≥1 foot grounded except at a jump's airborne apex; stay inside human joint ranges and keep weight over the support — see balance-and-posture.