Measuring the Obvious 🔍

A Human Factors Engineering Analysis of Kiosk Accessibility

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By: Mark Ogra
Shaaz Rizvi
Aaron Elrington-Edwards

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Introduction

Human Factors Foundation

  1. Fitts' Law & Target Acquisition
    • Touch target difficulty ∝ distance/size ratio
    • 172cm height + small UI = computational nightmare
    • Fixed angle compounds motor planning issues

Human Factors Foundation (cont.)

  1. Cognitive Load Theory

    • Physical strain increases cognitive overhead
    • Error recovery requires additional reaching
    • Time pressure compounds both issues

  2. Norman's Design Principles

    • Visibility compromised by physical design
    • Feedback requires additional physical effort
    • Mapping ignores natural affordances

Problem Space Overview


Interconnected barriers require systematic analysis

Current Implementation Issues

  • Fixed designs violating ergonomic standards
  • Conflicting accessibility accommodations
  • Environmental factors impacting usability
  • Resource allocation revealing priorities

Methodology

Initial Research Steps

  1. Initial Approach (Failed)
    • Attempted traditional user testing
    • Proposed menu item compensation
    • Received justified criticism
    • Recognized ethical issues
  1. Research Pivot
    • Developed measurement protocol
    • Created evaluation form
    • Obtained survey permission
    • Established documentation

Data Collection & Analysis

  1. Data Collection
    • Physical measurements
    • Survey distribution
    • Environmental documentation
    • Interface workflow
  1. Analysis Protocol
    • ADA standards review
    • Statistical analysis
    • Correlation studies
    • Cost-benefit evaluation

Tools & Equipment

  • Standard measuring tape (physical dimensions)
  • Digital level application (screen angles)
  • Survey instruments (user feedback)
  • Documentation templates (standardization)

Participant Demographics

  • Medical office setting providing diverse sample
  • Natural inclusion of mobility device users
  • Age range: 18-65+
  • Multiple accessibility needs represented

Mathematical Validation

Fitts' Law Application

where:

  • D = effective distance (cm)
  • W = target width (cm)

Kiosk Configuration Analysis

Comparative Results:

  • Standing (50cm reach): ID = 8.48 bits
  • Seated (70cm reach): ID = 8.54 bits
  • Additional cognitive load from non-optimal viewing angle

Physical Analysis

Measurement Results vs Standards

Component Measured ADA Requirement Citation Impact
Total Height 172cm 121.9cm max §308.2.1 Forward Reach ❌ Exceeds by 50.1cm
Screen Center 80cm 38-121.9cm §308.2.1-2 Reach Ranges ⚠️ Fixed at median
Payment Zone 68-92cm 38-122cm §308.3.1 Side Reach ⚠️ Upper range violation
Clear Space ~50cm 76cm min §305.3 Clear Floor ❌ 34.2% below min
Screen Angle Fixed -1° Adjustable §309.4 Operation ❌ No accommodation

Accessibility Conflicts: Physical Design

  1. Height vs Visibility
    • Lower placement helps wheelchair users
    • Creates strain for standing users
    • Current "solution" ignores principles
    • No single fixed height optimal
  1. Space vs Throughput
    • Wider spacing aids mobility
    • Conflicts with density goals
    • Reveals volume prioritization
    • ADA minimums as maximum

Accessibility Conflicts: Interface

  1. Interface Scaling Paradox
    • "Wheelchair mode" reduces element size
    • Directly conflicts with visual accessibility
    • Creates false choice between physical and visual access
    • Demonstrates fundamental design failure

System Evaluation

Demographic Representation

  • Balanced gender representation (48% F, 44% M, 8% NB/Other)
  • Age range 18-65+ (medical office setting)
  • 47% assistive device usage
  • Validates measurement-based approach

Physical Impact Analysis

  • 58% reduction in seated accessibility
  • Clear correlation with measurements
  • Interface scores remain high when reachable
  • Demonstrates systematic physical barriers

Empirical Evidence

  1. Key Findings

    • Screen height dominates (n=8)
    • Physical issues exceed interface problems
    • Observable without exploitation

  2. Impact Analysis

    • 50% drop in physical ease
    • Interface usable when reachable
    • Systematic barriers confirmed

Implementation Analysis

Technical Architecture

Current implementation specifications:

  • Intel Core i5-4570TE processor
  • 4GB DDR3 RAM
  • 128GB SSD
  • Windows 10 OEM license
  • Fixed mounting system

Resource Analysis

Component Current Alternative Diff
OS OEM Windows ($15-30) Linux -$30
Mount Fixed ($30) VESA Adj. +$30
Display Standard Anti-glare +$15
Total $500 $530 +$30

Priority Issues

  • Over-specified computing resources
  • Under-specified accessibility features
  • Cost optimization misaligned with usability

Methodological Critique

The Theater of Validation

  • Recruits marginalized users to prove obvious barriers
  • Generates data justifying inadequate solutions
  • Places burden of proof on affected populations

Cost-Benefit Analysis

Current Costs

Component Cost
Windows License $15-30
Fixed Mount $30
Standard Display Base
Per Unit ~$500

Business Impact

  • High proportion of sample used assistive devices
  • Increased service time
  • Staff intervention needed
  • Lost revenue from abandonment

Recommendations

Physical Changes

  • VESA-compatible mounts
  • Anti-glare treatment
  • Module placement
  • Clear space compliance

System Changes

  • Responsive design
  • Multimodal interaction
  • Error recovery
  • Universal design focus

References

  1. U.S. Department of Justice. (2010). 2010 ADA standards for accessible design. Retrieved from https://www.ada.gov

  2. Fitts, P. M. (1954). The information capacity of the human motor system in controlling the amplitude of movement. Journal of Experimental Psychology, 47(6), 381–391.

  3. Norman, D. A. (2013). The design of everyday things. Basic Books.

  4. u/tamay-idk. (2023, January 24). Specs of a McDonald's kiosk in more detail [Online forum post]. Reddit. https://www.reddit.com/r/PBSOD/comments/10kc86g/specs_of_a_mcdonalds_kiosk_in_more_detail_youre/

    ⚠️   The specifications shared in the Reddit post were independently verified through system inspection.

  5. Kim, C., Lee, J., & Bae, I. (2023). Comparative analysis of usability and accessibility of kiosks for people with disabilities. Applied Sciences, 13(5), 3058. https://doi.org/10.3390/app13053058

Questions?

Some Starters

  • "What inspired you to focus on kiosks?"
  • "How did the businesses respond?"
  • "Did you encounter any unexpected results?"

Going Deeper

  • "Could this apply to other interfaces?"
  • "What's the most cost-effective fix?"
  • Feel free to ask anything else!