---
pretty_name: ts-polyline-v2
tags:
  - robotics
  - navigation
  - terrasentia
  - polyline
  - trajectory
  - vqa
---

# ts-polyline-v2

[`adipotnis/ts-polyline`](https://huggingface.co/datasets/adipotnis/ts-polyline)
with every derived label baked in as columns — no sidecar files, no
training-time joins. One row = one camera frame with its future driven
trajectory and **all** supervision signals side by side.

TerraSentia (wheeled field robot) navigation from 22 ROS bags. Per frame: the
next 15 m of EKF odometry sampled at 0.25 m steps (up to 60 waypoints),
projected into the ZED camera as a pixel-space polyline and rendered as an
overlay. Every label is derived from the robot's own logs — no human
annotation.

## Summary

- Total samples: **108,491** (22 bags)
- `collision`: **16,372** (15.1%) · `reversing`: **26,300** (24.2%)
- Named surface transitions: **9,655** across **8,269** rows
- `usable` (surface labeling gate): **71,050** (65.5%); **10,793** rows
  geometry-rejected (polyline projects into an obstacle within 1 m —
  wall-projection artifacts)
- Wheel-slip coverage: **99%** of frames scoreable; traction mean **90.3**
  (p10 82, p90 98, 0–100 scale)
- Object descriptions: **20,000** frames

## Schema

All v1 columns are unchanged (`image`, `image_overlay`, `depth` [16-bit PNG,
mm], `traversability`, `polyline_xy`, `traj`, `collision`,
`time_to_collision`, `reversing`, ids). New columns:

| Field | Type | Notes |
|---|---|---|
| `surface_seq` | List[string] | canonical ground-surface label per waypoint (Mask2Former-COCO-panoptic, synonym-merged vocabulary: pavement/sidewalk/path/road are ONE class; `offground` = non-ground) |
| `transitions` | List[struct] | named surface crossings along the path: `{from_surface, to_surface, x, y, waypoint_start, waypoint_end}`, x/y normalized image coords |
| `offground_frac` | float | fraction of waypoints on non-ground classes |
| `geom_ok` | bool | False = the drawn path enters an obstacle within 1 m arc (depth-walk test) — projection artifact, exclude from path tasks |
| `collision_arc_m` | float | arc length to the first waypoint whose scene depth is shorter than its forward range; −1 if the path is clear |
| `collision_point` | List[float] | `[x, y]` normalized coords of the blocking pixel; `[]` if clear |
| `usable` | bool | `geom_ok and offground_frac <= 0.5` |
| `slip_seq` | List[float] | wheel slip in [0,1] at the moment the robot actually crossed each waypoint: `1 − v_EKF / mean(|wheel linear_speed|)` from `/terrasentia/motors` vs EKF; −1 = no valid wheel sample (wheel speed < 0.3 m/s or > 0.5 s gap). Traction = 1 − slip |
| `objects` | string | JSON list of visible objects `{label, cx, cy, bin}` (normalized center, near/mid/far distance band) from SAM3 detections + depth; `""` where not computed |

## Label provenance

- **Surfaces/transitions**: `facebook/mask2former-swin-large-coco-panoptic`
  semantic segmentation, canonical word-matched vocabulary; crossings need
  ≥3-waypoint runs each side, narrow unknown gaps (≤5 waypoints) bridged.
- **Collision geometry**: per-waypoint comparison of measured scene depth vs
  the waypoint's robot-frame forward range.
- **Slip**: two independent logs (wheel encoders vs EKF body speed) sampled
  at each waypoint's interpolated traversal time — *experienced* traction,
  complementing the camera-predicted `traversability` map.
- Build scripts: `ts-polyline-pipeline` (`scripts/build_ts_polyline_v2.py`
  and the sidecar builders it consumes).

Access is manually gated — request access and briefly say what for.