Dataset

SensorCaps

LLM-generated IMU captions (35,960 pairs) from HHAR/MotionSense/Shoaib/UCI-HAR/PAMAP2 (+ in-the-wild phones); TimeNet bash-lab/sensorcaps

Released with LLaSA (Large Language and Sensor Assistant; Imran et al., UbiComp Companion 2025 / arXiv 2406.14498). Pipeline: take windows from public HAR sets → downsample IMU to 10 Hz, round to 6 decimals → prompt GPT-4o-mini with activity summary + raw IMU + handcrafted features (FFT, min/max/median/variance, …) → emit (1) ≤25-word motion caption and (2) longer temporal narration. Soft labels: captions are LLM-generated, not human narrations.

At a glance
Type
Dataset
DOI
Not reported
Licence
Not reported
Access
Not reported
Subjects
Not reported
Signals
IMU
PPG sites
None
Setting
In the wild, Lab
Wrist
Yes
Raw waveforms
No
Tasks
Not reported
Updated
Nov 10, 2026

Original description

SensorCaps is an LLM-assisted softly-labelled IMU sensor data captioning dataset with feature summarizations and narrations of human activities.

Wearable systems can recognize activities from IMU data but often fail to explain their underlying causes or contextual significance. To address this limitation, we introduce two large-scale resources: SensorCap, comprising 35,960 IMU–caption pairs, and OpenSQA, with 199,701 question–answer pairs designed for causal and explanatory reasoning. OpenSQA includes a curated tuning split (Tune-OpenSQA) optimized for scientific accuracy, narrative clarity, and diagnostic insight. Leveraging these datasets, we develop LLaSA (Large Language and Sensor Assistant), a family of compact sensor-aware language models (7B and 13B) that generate interpretable, context-rich responses to open-ended questions grounded in raw IMU data. LLaSA outperforms commercial LLMs, including GPT-3.5 and GPT-4o-mini, on benchmark and real-world tasks, demonstrating the effectiveness of domain supervision and model alignment for sensor reasoning.

Verbatim fromHugging Face· Description from the Hugging Face card; licence as stated on the card

SensorCaps: ChatPPG research summary card

Key numbers

1
Reference labels
ACTIVITY
100 Hz
Released sampling rate
SensorCaps release: IMU resampled/serialized at 10 Hz (≤100 timesteps, 6 decimal places); source rates vary (HHAR device-max; MotionSense/UCI-HAR/Shoaib ~50 Hz; PAMAP2 IMU 100 Hz)

How it works

How SensorCaps works: Devices & body sites → Signals recorded → TasksDevices & body sites: None (PPG site). Signals recorded: SensorCaps, 100 Hz, signals IMU.Devices & body sitesNone: PPG siteNonePPG siteSignals recordedSensorCaps100 HzxyzIMU

No model in the hub reports results on this dataset yet.

Sampling
SensorCaps release: IMU resampled/serialized at 10 Hz (≤100 timesteps, 6 decimal places); source rates vary (HHAR device-max; MotionSense/UCI-HAR/Shoaib ~50 Hz; PAMAP2 IMU 100 Hz)
Reference labels
activity

Papers using this dataset· 1

#111 of 158 most-used datasets by published papers and models · #50 of 70 IMU

Cite

No citation metadata yet.

Cite the ChatPPG record

Cite the dated snapshot 2026-10 for a fixed, reproducible version. Please also cite the original publications listed above.

APA

ChatPPG. (2026). SensorCaps: dataset record (Version 2026-10) [Data set]. ChatPPG Research Hub. https://chatppg.com/research/datasets/sensorcaps

BibTeX
@misc{chatppg_dataset_sensorcaps,
  author       = {{ChatPPG}},
  title        = {{SensorCaps: dataset record}},
  year         = {2026},
  month        = nov,
  version      = {2026-10},
  howpublished = {\url{https://chatppg.com/research/datasets/sensorcaps}},
  note         = {ChatPPG Research Hub, Snapshot 2026-10, https://chatppg.com/research/snapshots/2026-10}
}
CITATION.cff
cff-version: 1.2.0
message: "If you use this resource, please cite it as below."
type: dataset
title: "SensorCaps: dataset record"
authors:
  - name: "ChatPPG"
url: "https://chatppg.com/research/datasets/sensorcaps"
repository-artifact: "https://chatppg.com/research/snapshots/2026-10"
version: "2026-10"
date-released: "2026-11-10"

History

  1. Record updated