Papers for

assistive technology developers

Papers whose findings have a practical use for this group, as judged from the abstract. Open a paper to read what it means in practice.

Vision language models assist spatial navigation for visually impaired users

Assisted Spatial Cognition Through Vision-Language Models

Abstract: Multimodal AI, powered by Large Language Models (LLMs) and Vision-Language Models (VLMs), is transforming assistive technologies by enabling simultaneous processing of visual and textual data. This advancement holds significant promise for over 43 million visually impaired and neuro-divergent individuals worldwide who face persistent challenges in navigating indoor and outdoor environments due to limited spatial awareness and insufficient environmental cues. Existing navigation aids often lack comprehensive 3D scene understanding, relying on constrained route-based strategies that hinder user autonomy. In this paper, we introduce a novel end-to-end framework that integrates LLMs, VLMs and digital twin technologies to deliver a spatially cognitive navigation support for visually impaired and neuro-divergent users. Our system captures video input via standard mobile phone cameras, and employs SLAM3R to generate dense 3D point clouds from monocular RGB sequences in real-time. Our custom post-processing algorithm ensures accurate point cloud alignment across multiple viewpoints without requiring predefined reference points. This enhances the capabilities of SpatialLM to produce structured 3D representations, including architectural elements and oriented object bounding boxes. The enriched spatial data is then processed by a locally deployed LLM, which interprets 3D contexts to generate detailed scene descriptions and precise distance measurements between users and surrounding objects. We evaluated our approach across diverse video scenarios featuring various perspectives, looped walking views and captured in multiple environments. The evaluation results demonstrate consistent accuracy in 3D scene interpretation and object localisation, underscoring the potential of our system as a transformative assistive navigation solution that combines advanced visual perception with spatial reasoning

Fri 11 SeptArtificial Intelligence
The gist
Many people who are visually impaired or have different cognitive needs find it hard to understand and navigate their surroundings. This paper presents a new system that uses phone cameras to create detailed 3D maps of places in real time. The system combines smart language and vision AI models to describe spaces clearly and accurately, helping users understand where things are around them. The authors tested their system in many settings and showed it works well for giving detailed directions and object locations.
Open 2609.12747v1

Browser tool creates printable braille and tactile storybooks on demand

Tact: A Zero-Cost, Browser-Based Pipeline for On-Demand Tactile Braille Storybooks

Abstract: Braille literacy among blind school-age children has fallen sharply, in part because producing illustrated braille pages still requires specialized software and trained labor. We present Tact, a browser-based pipeline that converts a spoken or typed story idea into printable braille with a matching raised tactile illustration, without an account or mandatory cost and with an offline-capable path. The paper documents the engineering history of the system: its sighted-operator ethical model; hardware rationale for consumer fused-deposition modeling; physical braille geometry and printer calibration; local, hosted, and fallback language-model paths; a deterministic Grade 1 braille translator; verified page layout and pagination; a 93-shape hand-drawn tactile illustration library; and synthesized sound design for a voice-first interface. We report engineering verification, ethical commitments, limitations, and the work required before the system is ready for real blind and low-vision readers.

Thu 10 SeptHuman-Computer InteractionComputers and Society
The gist
Braille reading skills among blind children are declining partly because making illustrated braille books requires special tools and trained people. The authors created Tact, a tool that anyone can use in a web browser to turn spoken or typed stories into braille pages with matching raised pictures. This tool works without needing an account, internet connection, or extra costs, and it uses simple 3D printers common at home. The authors describe how they built and tested the system, including how the braille and images are made, how it handles different languages, and the ethical rules for using it.
Open 2609.12272v1

Random forest classifies real and imagined motor EEG signals accurately

Electroencephalography Signal Analysis for Human Activities Classification: A Solution Based on Machine Learning and Motor Imagery

Abstract: Electroencephalography (EEG) is a fundamental tool for understanding the brain's electrical activity related to human motor activities. Brain-Computer Interface (BCI) uses such electrical activity to develop assistive technologies, especially those directed at people with physical disabilities. However, extracting signal features and patterns is still complex, sometimes delegated to machine learning (ML) algorithms. Therefore, this work aims to develop a ML based on the Random Forest algorithm to classify EEG signals from subjects performing real and imagery motor activities. The interpretation and correct classification of EEG signals allow the development of tools controlled by cognitive processes. We evaluated our ML Random Forest algorithm using a consumer and a research-grade EEG system. Random Forest efficiently distinguishes imagery and real activities and defines the related body part, even with consumer-grade EEG. However, interpersonal variability of the EEG signals negatively affects the classification process.

Thu 10 SeptNetworking and Internet Architecture
The gist
Understanding brain signals when people move or imagine moving can help develop tools controlled by thoughts. The authors used a machine learning method called Random Forest to identify whether brain signals come from actual movements or imagined ones and also which body part is involved. They tested their method on two types of EEG devices, including a consumer-level one, and it worked well. However, brain activity patterns vary between people, which makes classification harder.
Open 2609.11695v1

P300 speller components can reduce performance when combined

When More Is Not Better: Component Anti-Synergy in a P300 Speller

Abstract: P300 brain-computer interface (BCI) spellers can provide hands-free communication for people with severe motor impairments. Modern pipelines combine multiple individually promising components, often assuming that 'more-is-better'. We tested this assumption using a four-component full-factorial experiment varying the inclusion of Euclidean Alignment (EA), xDAWN spatial filtering, subject calibration, and language model priors on a public P300 dataset. Performance was evaluated using accuracy, repetitions, and information transfer rate (ITR) with mixed-effects models. Results show that the value of components is conditional rather than additive. Calibration was the strongest singular contributor, while EA compensated for its absence in zero-calibration settings. Adding independently useful components could also reduce performance, revealing component anti-synergy. Contrary to conventional wisdom, LM support was not universally beneficial: its effect depends strongly on the strength of the underlying EEG pipeline, while results from a larger LM showed a similar pattern. Together, these findings challenge maximal 'all-on' pipeline design and highlight the value of selecting spatial and language-support components according to the quality of available EEG evidence.

Thu 10 SeptMachine Learning
The gist
People with severe movement problems can use brain signals to spell words without using their hands. This paper shows that adding more helpful tools to a brain-computer interface doesn't always improve how well it works. Different parts like calibration, signal processing, and language help don't just add up; sometimes they interfere with each other. The researchers found calibration is very important, and some tools only help when calibration is missing. This challenges the idea that turning on everything is best for these devices.
Open 2609.10961v1

Non-invasive brain recordings decode sentence meaning into text

The Semantic Bottleneck: Leveraging Semantic Representations for Non-Invasive Speech Decoding

Abstract: Non-invasive speech decoding remains constrained by the low signal-to-noise ratio of neural recordings, which makes fine-grained reconstruction of phonemes or individual words difficult. Motivated by neuroscientific evidence that high-level semantic representations are distributed across cortical regions and evolve over slower temporal scales, we hypothesize that semantic content may provide a more suitable target for non-invasive decoding than low-level acoustic or lexical features. We introduce Brain2Semantics2Text, a method that reconstructs text through an intermediate semantic embedding space. Our model maps sentence-level MEG responses into a semantic manifold and then inverts the predicted embeddings into natural language. This semantic bottleneck enables recovery of high-level meaning without word-level alignment. We describe the core principles of the approach, its implementation, and the strategies used to mitigate the challenges of learning a reliable neural-to-semantic mapping. Finally, we compare against prior non-invasive Brain2Text methods and show improved sentence-level results.

Wed 9 SeptComputation and LanguageMachine Learning
The gist
Decoding spoken words from brain signals is usually hard because these signals are noisy. The authors found that targeting the overall meaning of sentences, rather than individual sounds or words, works better for non-invasive brain recordings. They created a system that first translates brain signals into a kind of meaning representation, then turns that into text. This approach helps recover what was being thought more accurately without needing exact word-by-word matching.
Open 2609.10296v1

Deaf users help design better text to speech technology

Seeing the Voice, Preserving the Self: A Participatory Design Approach to Deaf-Centric Text-to-Speech

Abstract: We describe a participatory design approach toward developing Deaf-centric text-to-speech (TTS) technologies. While TTS is growing rapidly in the mainstream, it has received little attention to date in the deaf and hard of hearing (DHH) technology space. Critical problems have remained unaddressed for DHH users, including the ability to manipulate tone, emotions and delivery via non-auditory means. Verifying that the generated speech matches intent and is appropriate for a given situation without having to listen to it is another challenge. Respecting cultural and identity factors in the generated speech is also important. This work explores the design space with DHH participants through two focus groups, three co-design sessions, and four one-on-one early-stage design evaluation sessions. Participants included people both familiar and unfamiliar with TTS, as well as DHH content creators. We describe key findings, design ideas, results, and implications for future Deaf-centric TTS development. We also identify unmet technology requirements that pose barriers to adoption of Deaf-centric TTS technology.

Wed 9 SeptHuman-Computer Interaction
The gist
Text-to-speech (TTS) technology is common, but it doesn't work well for deaf or hard of hearing people because it lacks ways to control tone and emotion without sound. The authors worked closely with deaf participants to explore how TTS systems can be designed to fit their cultural and communication needs better. They found challenges like confirming the speech’s meaning visually and respecting identity in the voice style. Their work reveals what features and design ideas are currently missing for TTS to be truly useful for deaf users.
Open 2609.10199v1

P300 brain signal captured reliably across five EEG headsets

Streaming P300 Acquisition and Statistical Signal Validation Across Five EEG Platforms: A Hardware-Agnostic BrainFlow/LSL Pipeline

Abstract: P300 spellers offer people with severe motor impairment, such as ALS, an effective communication channel and remain one of the most established surgery-free alternatives to intracortical interfaces. Advanced language models have made spellers faster and more robust, yet the hardware beneath them is under-studied. We present a hardware-agnostic, real-time P300 acquisition pipeline built on BrainFlow and Lab Streaming Layer (LSL) that runs unchanged across consumer- and research-grade EEG headsets, with permutation tests of signal separability. Using a standard 6 x 6 row/column paradigm, we piloted five configurations: a custom dry system, a custom wet/gel system, Emotiv Flex, Emotiv EPOC X, and Muse 2. The custom systems and EPOC X showed weak or inconsistent signal separability, Muse 2 had the highest acquisition reliability despite limited centro-parietal coverage, and Flex showed the most promising signal. In 20 further Flex sessions varying subject, timing, and phrase length (131 target characters), a peak-amplitude permutation test and a cross-validated xDAWN decoder both detected a significant target response under two channel-exclusion policies, with decoder AUC reaching about 0.72 after 15 repetitions. Character accuracy depended heavily on evaluation methodology: in-sample majority voting reached 94.7%, whereas character-held-out accuracy was 31.3% with evidence accumulated across repetitions, about three times that of held-out majority voting. These analyses indicate that Flex captured a detectable, if still weak, P300 under the studied conditions, while broader participant-level validation and improved decoding remain necessary.

Wed 9 SeptHuman-Computer Interaction
The gist
People with severe motor disabilities can communicate using brain signals called P300, detected by EEG devices. The authors built a system that works in real-time with different EEG headsets without needing special adjustments. They tested five headsets and found that some, like the Muse 2 and Emotiv Flex, detected the P300 signals better than others. Although signals were still weak in some cases, their flexible system showed it is possible to capture these responses broadly and consistently. More work is needed to improve decoding accuracy and test with more participants.
Open 2609.10047v1

Marker-free eye-gaze tracking using single camera and defocus depth

Marker-free eye-gaze estimation using a single image and depth from defocus

Abstract: This paper presents a marker-free eye-gaze estimation approach using a single 2D camera, such as an integrated laptop webcam. The gaze-related features are estimated from iris localization and head pose estimated by using depth from defocus. A variational Bayesian multinomial logistic regression framework is used as mapping from the estimated features to the position of regard, based on an 8-dimensional feature vector of head-pose and iris-displacement parameters. No external marker is needed. Experiments were conducted by estimating the gaze of people watching a computer screen at different distances and compared against five existing methods. The obtained scores demonstrate the effectiveness of the proposed approach.

Wed 9 SeptComputer Vision and Pattern Recognition
The gist
Tracking where someone is looking usually needs special markers or multiple cameras, but this paper shows a way to do it with just one regular 2D camera, like a laptop webcam. The method figures out where the iris is and the head’s position by looking at how out-of-focus the image is (depth from defocus). Then, it uses a smart math model to connect these features to where the person is looking on a screen. The authors tested this approach against other methods and found it worked well without needing any extra markers.
Open 2609.09610v1