Three Modalities, Two Design Probes, One Prototype, and No Vision: Experience-Based Co-Design of a Multi-modal 3D Data Visualization Tool
Organizations: School of Information Sciences, University of Illinois Urbana-Champaign, Champaign, Illinois, USA · Informatics, University of Illinois Urbana-Champaign, Champaign, Illinois, USA · School of Information, University of Michigan, Ann-Harbour, Michigan, USA · American Printing House for the Blind, Louisville, Kentucky, USA
Abstract
Three-dimensional (3D) data visualizations, such as surface plots, are vital in STEM fields from biomedical imaging to spectroscopy, yet remain largely inaccessible to blind and low-vision (BLV) people. To address this gap, we conducted an Experience-Based Co-Design with BLV co-designers with expertise in non-visual data representations to create an accessible, multi-modal, web-native visualization tool. Using a multi-phase methodology, our team of five BLV and one non-BLV researcher(s) participated in two iterative sessions, comparing a low-fidelity tactile probe with a high-fidelity digital prototype. This process produced a prototype with empirically grounded features, including reference sonification, stereo and volumetric audio, and configurable buffer aggregation, which our co-designers validated as improving analytic accuracy and learnability. In this study, we target core analytic tasks essential for non-visual 3D data exploration: orientation, landmark and peak finding, comparing local maxima versus global trends, gradient tracing, and identifying occluded or partially hidden features. Our work offers accessibility researchers and developers a co-design protocol for translating tactile knowledge to digital interfaces, concrete design guidance for future systems, and opportunities to extend accessible 3D visualization into embodied data environments.
Figures & tables
| Canonical EBCD Stage | Our Adaptation and Rationale |
|---|---|
| Setting up the project | We established our co-design team, clarified roles, and oriented BLV researchers to both the tactile and digital phases, ensuring a shared understanding and equal power in design. |
| Gather staff / practitioner experiences | In our context, “staff” maps to non-BLV researcher; we collected their perspectives on constraints and design possibilities, balancing with BLV lived experience. |
| Gather patient / user experiences | We ran low-fidelity and high-fidelity design probe sessions and narrative interviews to collect first-person accounts of exploring 3D surfaces non-visually. |
| Trigger film (or tangible trigger) | Instead of a video film, we used the tactile probe and semi-structured questioning to surface emotional and perceptual “touch-points” in how BLV collaborators explore surface features. |
| First co-design event | We brought BLV researchers together in our workshops, using prior experiential data to align on priorities and co-create interaction features through Session 1 and 2. |
| Co-design working groups | We iteratively developed our high-fidelity prototype (drawing from insights gathered during Session 1) and tested the final version with requested features (e.g., sonification and buffer aggregation) during Session 2. |
| Criterion | 2D Web-based Encodings | Physical Tactile Displays | Augmented Reality (AR) |
|---|---|---|---|
| Occlusion Handling | Cannot multi-modally represent depth or hidden structures and remain limited to surface projection for 3D surfaces ( Farshian et al., 2023 ) | Users must physically explore raised lines or pins, so occluded areas require manual navigation ( Zhao et al., 2021 ) | Can simulate 3D depth with audio or visual layering, but hidden or overlapping features may still be difficult to disambiguate for non-visual users ( Marquardt, 2023 ) |
| Persistence | Encoding via color, glyphs, or text is not appropriate for non-visual access due to high cognitive load ( Syvertsen, 2022 ) | Physical relief or pins remain until manually reset, but reconfiguration may be limited to pre-existing states ( Je et al., 2021 ) | AR augmentations persist only while the device is held and tracked; tracking errors or device movement can break spatial consistency ( Grimm et al., 2022 ) |
| Resolution for Continuous Surfaces | Limited by the granularity of encoding (e.g., color bins, glyph size) ( Song et al., 2025 ) | Limited by pin density or embossing precision; highly detailed surfaces are hard to render affordably ( Bhatnagar et al., 2023 ) | High potential: AR can render very fine-grained spatial structure digitally, but non-visual sensing is currently limited ( Creed et al., 2024 ) |
| Co-location Requirement | Users can access remotely via personal devices such as laptops and mobile phones ( Seo et al., 2024b ; Zhang et al., 2024 ) | User must have the tactile display physically present but do not require co-location with others | AR devices (e.g., headset or phone) must be co-located with the physical space or digital model ( Geary et al., 2022 ) |
| Cost | Very low: software solutions are inexpensive | Often high: refreshable tactile displays or embossers are expensive to build or buy ( Mukhiddinov and Kim, 2021 ) | High: AR headsets or development of specialized AR for accessibility can be costly ( Amer and Peralez, 2014 ) |
| Web Integration | Excellent: software and web-native systems are naturally integrated ( Seo et al., 2024b ) | Many tactile displays operate using specialized drivers and often require extensive troubleshooting | Moderate to low: AR systems are often standalone applications and not deeply web-integrated ( Rafdhi, 2024 ) |
| Name | Visual Acuity | Age of Onset | Age | Occupation |
|---|---|---|---|---|
| Sanchita | Not BLV; corrected to 20/20 with lenses | Not applicable | 24 | Graduate Teaching and Research Assistant |
| Aziz | No vision in left eye; 20/2000 in right eye | Congenital | 28 | Graduate Teaching and Research Assistant |
| Venkatesh | Totally Blind | Congenital | 32 | Assistant Professor of Information |
| Sile | Some light perception | Congenital | 59 | Professor of Information |
| Ken | Totally Blind | 20 | 55 | Senior Software Engineer and R&D Specialist |
| JooYoung | No light or shape perception in right eye, light and shape perception in left eye | 11 | 35 | Assistant Professor of Information Sciences |
| Prompt | Analytic Task | Observed Issue | Design Change Implemented |
|---|---|---|---|
| “How do you know where you are in the plot? What cues help you understand the axes?” | 3D Orientation | Axis convention misalignment: co-designers expected Y-axis on board, Z-axis pointing out; digital used Y-vertical, Z-depth. Ken: “I would expect the y-axis to be on the board and the z-axis pointing out.” Venkatesh: “X-axis would be along the horizontal edge of the board, Y-axis would be along the vertical edge… and Z-axis would be the one popping.” | Fixed reference sonification at origin (0,0,0) via 0-key; replay mechanism via .-key to re-hear current position ( DG3 ). |
| “Can you follow the path of steepest ascent? How would you trace a ridge or valley?” | Gradient Tracing | Lack of spatial encoding for horizontal and depth dimensions. Venkatesh: “it would be nice to have it pan from left to right, and decrease the volume as it’s going forward.” | Stereo panning for X-axis (left-right), volumetric audio (volume + reverb) for Z-axis depth ( DG4 ). |
| “What would help you compare multiple high points?” | Comparing Local Maxima vs. Global Trends | Difficulty maintaining mental representation of previous positions during sequential exploration; physical probe allowed simultaneous tactile comparison. | Configurable buffer: drag-select to save region, toggle between aggregated (mean) and sequential (point-by-point) playback via G-key ( DG5 ). |
| “How would you explore areas that might be hidden from one perspective?” | Identifying Occluded Features | Inter-plot comparison not supported; need to differentiate datasets by categorical variable. Ken: “What if I wanted to compare two sets of data… Is there any way to overlay them and switch between the two surfaces?” Sile: “if you gave the sound for Georgia a square wave instead of a sine wave.” | Identified for future implementation: dual-dataset overlay with distinct timbres and keybinding toggle. |
| Feature | Test Prompt | Result & Co-designer Quote | Next Steps / Refinements |
| Reference Sonification & Replay ( DG3 ) | “Navigate away from the origin and use the reference key to reorient yourself.” | Success. Sile: “it does help, actually… having it separate like that, but allowing you to play either coincidentally or in sequence, that’s really nice.” Venkatesh: “that was the main observation I had, but I think it’s pretty cool that I get to hear the reference point.” | None required; feature successfully validated for orientation restoration. |
| Stereo & Volumetric Audio ( DG4 ) | “Trace a horizontal path and describe the spatial cues you perceive.” | Partial success. Stereo panning validated. Sile: “(stereo panning) it actually has been very interesting.” Volume for depth too subtle. Sile: “(volume) I couldn’t notice it that much.” | Add reverb to depth encoding. JooYoung: “Using volume only may not be sufficient, so I suggest using echo sound (reverb)…if you combine volume plus, echo, then, it will be more pronounced.” |
| Configurable Buffer ( DG5 ) | “Select a region, compare its aggregated sound to individual points, then compare the region to a different area.” | Partial success. Concept validated, interaction issues surfaced. Venkatesh: “why…I mean, just flip the order of actions, right? Like, first go to the point that you want to start selection from, and then when you press D, the backend knows.” Ken: “I’m wondering…How this is useful… what am I getting from that?” | Redesign interaction: anchor selection at current position on first D-press. Add boundary entry/exit announcements. Venkatesh: “my use case for suggesting this is comparing whatever you might hear in aggregate to individual points.” See Table 6 for prioritized fixes. |
| Priority | Usability Issue | Co-designer Quote / Observation | Proposed Fix |
| P1 | Two-step selection initiation breaks flow; users must navigate away, press D, navigate to start point, press Enter. | Venkatesh: “why…I mean, just flip the order of actions, right? Like, first go to the point that you want to start selection from, and then when you press D, the backend knows.” | Anchor selection at current position on first D-press; eliminate redundant Enter step. |
| P2 | Lack of boundary awareness; users cannot tell when they re-enter or exit the selected region during subsequent navigation. | Venkatesh: “it would be nice if, as you’re navigating around…it announces when you enter the region or when you leave the region.” | Add audio announcement when cursor crosses buffer boundary; consider persistent background cue (e.g., subtle ambient tone) while inside region. |
| P3 | Aggregated playback purpose unclear; co-designers unsure when mean value is useful versus sequential point-by-point replay. | Ken: “I’m wondering…How this is useful… what am I getting from that?” Venkatesh clarified: “my use case for suggesting this is comparing whatever you might hear in aggregate to individual points.” | Provide contextual help (e.g., on-demand description of aggregation modes); add example prompts in tutorial demonstrating comparison workflow. |
Appendix figures & tables1 asset
Supplementary material from the paper’s appendix.