Advancing Accessible Bus Transit: Human-Machine Interfaces for Inclusive Communication and Safe Boarding of Passengers with Disabilities

This research focuses on co-designing and testing innovative rider communication tools to enable passengers with disabilities to effectively signal their intent to board public bus transit. People with disabilities often face challenges in visually or physically signaling their needs at bus stops, leading to missed rides, inadequate assistance, and reduced confidence in transit systems. By developing human-machine interfaces (HMIs) that facilitate clear communication between riders and drivers, this project aims to improve access to public transit. Inspired by advancements in V2X communication, the U.S. Department of Transportation has demonstrated the potential of rider-to-vehicle communication through initiatives like the Integrated Dynamic Transit Operation System (IDTO) (Meng et al. 2018). In this system, riders could use an app to request connection protection, relayed to drivers via dispatchers, reducing wait times at transfer points by an average of seven minutes. Similar systems, such as flex-routing, allow riders to request pickups near fixed routes, addressing access in rural areas (e.g., Skagit Transit). While these approaches demonstrate the value of pre-trip communication, they primarily target specific scenarios and do not fully address the needs of passengers with disabilities, particularly those who cannot visually discern approaching buses or signal drivers effectively (Greer et al. 2014, Steinfeld et al. 2019). To address these gaps, the research team will conduct participatory design workshops with transit riders, drivers, and advocacy groups to guide the creation of rider communication systems. These workshops will provide collaborative spaces for sharing experiences, identifying unmet needs, and developing solutions through activities like brainstorming, low-fidelity prototyping, and role-playing real-world scenarios. Insights from these sessions will inform functional prototypes, such as mobile apps or physical interfaces at bus stops. Simulated experiments will evaluate the impact of these tools on driver workload, operational safety, and rider satisfaction. These experiments will also assess how HMIs help drivers assist passengers while minimizing distractions and maintaining safety standards. For example, the team will analyze how notifications via mobile apps or visual indicators at bus stops can aid drivers in identifying and assisting riders while avoiding information overload that could compromise situational awareness. Additionally, by accounting for various scenarios—such as varying weather conditions, crowded bus stops, and different disabilities—the tools will aim to address real-world challenges. The team will also evaluate the timing and content of communications to optimize their effectiveness for drivers and riders alike. This participatory approach seeks to create communication systems that reduce barriers to mobility for passengers with disabilities, ensuring access to public transit. This research contributes to the broader goal of building safer transit systems.

• Record URL:
  • https://ppms.cit.cmu.edu/projects/detail/642

Language

• English

Project

• Status: Completed
• Funding: $200,000.00
• Contract Numbers:

  69A3552344811

  69A3552348316

• Sponsor Organizations:

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590
• Managing Organizations:

  Safety21 University Transportation Center

  Carnegie Mellon University
  Pittsburgh, PA  United States  15213

  Carnegie Mellon University

  Pittsburgh, PA  United States 
• Performing Organizations:

  Carnegie Mellon University

  Pittsburgh, PA  United States 
• Principal Investigators:

  Fox, Sarah

  Martelaro, Nikolas

• Start Date: 20250701
• Expected Completion Date: 20260831
• Actual Completion Date: 20260831
• USDOT Program: University Transportation Centers

Subject/Index Terms

• TRT Terms: Accessibility; Bus drivers; Mobile applications; Persons with disabilities; Public transit; Signaling; Transit riders
• Subject Areas: Data and Information Technology; Passenger Transportation; Public Transportation; Safety and Human Factors;

Filing Info

• Accession Number: 02002864
• Record Type: Research project
• Source Agency: Safety21 University Transportation Center
• Contract Numbers: 69A3552344811, 69A3552348316
• Files: UTC, RIP
• Created Date: Sep 18 2026 10:09AM