From aria-ark
Use when working with Aria Machine Perception Services (MPS) — cloud-based processing of Aria VRS recordings for SLAM trajectories, hand tracking, semi-dense point clouds, and online calibration. Covers the aria_mps CLI, single and multi-sequence processing, output formats, data lifecycle, and loading MPS results with ProjectAriaTools. Use whenever the user mentions MPS, aria_mps, SLAM processing, cloud hand tracking, trajectory generation, or submitting VRS files for processing.
How this skill is triggered — by the user, by Claude, or both
Slash command
/aria-ark:mpsThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
MPS is a cloud-based post-processing service for Aria recordings. You submit VRS files via the `aria_mps` CLI, MPS runs proprietary Spatial AI algorithms, and you download the derived outputs (trajectories, point clouds, hand tracking). The data is only used to serve requests — not accessible to Meta researchers.
MPS is a cloud-based post-processing service for Aria recordings. You submit VRS files via the aria_mps CLI, MPS runs proprietary Spatial AI algorithms, and you download the derived outputs (trajectories, point clouds, hand tracking). The data is only used to serve requests — not accessible to Meta researchers.
This skill teaches concepts and capabilities. For details, use the authoritative sources:
aria_mps --help, aria_mps single --help, aria_mps multi --helphelp(projectaria_tools.core.mps) or MpsPyBind.h in the cloned repo. See the projectaria-tools skill.pip install projectaria-mps (automatically includes projectaria-tools and projectaria-vrs-health-check)aria_mps$HOME/.projectaria/mps.ini — concurrency, chunk sizes, retry logic.MPS provides three services. Services are independent — you can request any combination. VRS health check runs automatically before processing.
Check the versioning docs for current service versions and the benchmarks page for accuracy metrics.
aria_mps single): Process recordings independently. When pointed at a directory, recursively discovers all VRS files and processes concurrently (default 25, configurable up to 100).aria_mps multi): Process multiple recordings together for Multi-SLAM in a shared coordinate frame.--features: Select specific services (e.g. SLAM, HAND_TRACKING). Default: all applicable.--force: Bypass deduplication cache and reprocess.--no-ui: Headless mode for scripted/automated pipelines.The CLI executes stages sequentially: status check → health check → encryption → upload (resumable within 24h) → server processing → download. Quitting after upload lets processing continue in the background — results download automatically when you rerun.
Results are saved alongside the input VRS file in a sibling folder. The structure includes separate directories for each service (slam/, hand_tracking/) plus a VRS health check report. Each service folder contains data files (CSV/JSON) and a summary.json with quality metrics.
See the data formats docs for exact CSV column definitions, coordinate conventions, and timestamp semantics.
tracking_timestamp_us (device clock, monotonic, stable) is for time calculations. utc_timestamp_ns (wall clock) is NOT monotonic — avoid for durations.graph_uid: Identifies the world coordinate frame. Data sharing the same graph_uid is spatially consistent.quality_score: Per-pose confidence (0–1). Filter low-quality poses for downstream use.uid for per-frame 2D-3D correspondences.--force to bypass.On-device eye gaze and VIO are embedded in the VRS during recording (accessible via PAT Tutorial_4 and Tutorial_5). Cloud MPS produces substantially better results using offline algorithms — higher accuracy for both SLAM and hand tracking. See the benchmarks page for quantitative comparisons.
When any MPS command fails, returns unexpected output, or produces low-quality results, you MUST consult this section and the official troubleshooting page BEFORE attempting your own diagnosis. This is not optional. MPS failures have MPS-specific root causes (health check rejections, insufficient recording length, coordinate frame mismatches) that generic debugging will misdiagnose.
Anti-patterns:
--force wastes upload time and quota.Official troubleshooting page: https://facebookresearch.github.io/projectaria_tools/gen2/ark/support/mps — covers symptoms not listed below.
summary.json for per-service status (SUCCESS/WARNING/ERROR) and quality metricsnpx claudepluginhub facebookresearch/projectaria-plugins --plugin aria-arkProvides behavioral guidelines to reduce common LLM coding mistakes, focusing on simplicity, surgical changes, assumption surfacing, and verifiable success criteria.
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