Dept. of Transportation
Metro Transit Division

King Street Center
201 S Jackson St
Seattle, WA 98104
Metro Online Home

Executive Summary

I. Project Overview


In October 2001 through January 2002, King County Metro Transit and Sound Transit conducted the Regional Smart Bus Demonstration Project Phase 1, a short term, limited demonstration of off-the-shelf smart bus technology on two transit coaches. This report evaluates the results of the demonstration project, with an emphasis on technical approach, transit business impacts, and lessons learned from the demonstration. Another evaluation with a regional focus was conducted by a consultant hired by Sound Transit.


The purpose of the Smart Bus Demonstration project was to:

  • Demonstrate the capabilities of readily available "smart bus" onboard systems as the current level of technology available in the transit market;
  • Obtain real world experience with the advanced onboard systems functions to:
    • Provide input for King County Metro's OnBoard Systems project requirements development effort;
    • Identify the potential impact of fleet wide implementation;
    • Identify the potential benefits of implementing the technology.

The demonstration project was conducted without a detailed requirements development process, with the goal of incorporating lessons learned from the demonstration into better informed requirements for a system wide OnBoard Systems project procurement.

As a short-term installation, the demonstration equipment was not subject to the extensive, iterative testing and fine-tuning typical of permanent installations. As a result, this report describes the outcome of a short-term, preliminary exercise conducted to provide King County Metro transit staff and riders experience with the technology. The project was not intended to demonstrate the full capabilities of the technology under the optimum conditions of a longer-term installation.

It should be noted that the demonstration vendor did not participate in the demonstration evaluation activities conducted by King County Metro Transit and Sound Transit. The conclusions reported in this document are based on King County Metro Transit's understanding of the demonstration technology and evaluation assessments and results.


For the four-month demonstration, existing, integrated smart bus technology was installed on two transit coaches at the King County Metro Transit Central Base facility: one King County Metro New Flyer articulated coach which operated routes 5, 7, 54, 55 and 167, and a Sound Transit 40-foot Gillig coach, which operated Sound Transit Route 570.

The Smart Bus demonstration vehicles were equipped with an information system that determined the coach's location, schedule and time of day, and monitored the status of various vehicle components. An onboard network communicated and shared data among the components of the onboard system, and an onboard database collected the data generated by the systems in operation.

To limit the scope of the project, the demonstration equipment generally was not integrated with the existing onboard systems, such as the transit radio system. The demonstration system however, was integrated with the existing transit radio Mobile Data Terminal (MDT) to allow transit operators to initiate both systems with a single log in. The system monitored and collected data from existing vehicle maintenance systems, such as the transmission, engine and braking systems.

The onboard systems functions provided in the demonstration included:

  • GPS based vehicle location, schedule adherence, and on-route status;
  • Automated vehicle maintenance (AVM) data;
  • Automated passenger counting (APC) data collection;
  • Wireless data on/off load system (WDOLS);
  • Automated interior stop announcements of major stops and landmark information;
  • Automated interior next stop displays;
  • Automated exterior route and destination announcements;
  • Automated exterior route and destination signs;
  • The ability to transmit vehicle on-time status and passenger load to the King County Metro Transit Signal Priority (TSP) system.

King County Metro Evaluation Purpose

The purpose of the King County Metro Regional Smart Bus Demonstration Evaluation was to examine the demonstration equipment's technical approaches as examples of smart bus technology, and to capture lessons learned, and issues raised by the demonstration in preparation for the system wide onboard systems requirements development, procurement and implementation effort at KC Metro.

Caveat: This evaluation was designed to provide an opportunity for King County Metro Transit staff to become better informed about the nature of advanced transit technologies. The evaluation does not attempt to quantify, prove or disprove the validity, accuracy, or appropriateness of any technology discussed in this report.

Evaluation Objectives

The following objectives were used to evaluate the demonstration:

Objective 1: Examine the functions and technical approaches of the smart bus off-the-shelf onboard equipment in the King County Metro Transit environment.

Objective 2: Assess customer satisfaction with the automated announcements and interior signs.

Objective 3: Obtain transit staff and transit operator feedback on the new functions: ease of use, advantages and disadvantages.

Objective 4: Identify issues, lessons learned, and recommendations for potential system wide implementation of the smart bus onboard equipment.

Objective 5: Identify the potential long-term benefits of implementing smart bus technology.

II. Key Findings

Overall, the demonstration functions performed well in revenue service and received positive reactions from transit riders and King County Metro Transit staff who had an opportunity to experience the demonstration equipment. The demonstration allowed technical staff to learn how the various Smart Bus features could be deployed in the King County Metro operational environment.

Stakeholder Feedback

The Smart Bus Demonstration Project provided an opportunity to obtain feedback on smart bus functions from various stakeholder groups including:

Transit Riders

  • In an onboard survey of 469 Smart Bus Demonstration riders, the vast majority of survey respondents rated the interior stop announcements, interior next stop displays and exterior route and destination announcements as very or somewhat helpful.
  • Automated interior stop announcements: The vast majority of survey respondents indicated the announcements of major stops and transfer points typically were made at the right time, but a small percentage of respondents noted the announcements were made too late. Additional tuning of the Smart Bus system performance parameters is expected to further improve the timing of the announcements.
  • Automated interior next stop displays: The vast majority of onboard survey respondents rated the next stop displays as "very easy to see," and considered the information accurate. The next stop displays were the most preferred demonstration function, selected by 43 percent of respondents.

Riders with Disabilities

Sound Transits Citizen's Accessibility Advisory Committee (CAAC) and the Deaf-Blind Workgroup provided the following feedback on Smart Bus Demonstration functions:

  • Automated interior stop announcements: Discussion participants appeared satisfied with the interior stop announcements. Most participants rated the clarity and volume of the announcements, and the ability to hear the announcements over ambient noise, as good.
  • Automated interior next stop displays: Participants expressed concerns with the interior next stop display lettering color and the speed at which the information changed on the display. Issues with sign visibility were noted from glare and the placement of the sign over the front window of the 40-foot Gillig.
  • Automated exterior route and destination announcements: The exterior speaker on the 40-foot Sound Transit Gillig coach should be moved from mid-coach to near the front door to allow people with visual disabilities to orient themselves to the entrance of the coach and hear the announcements more clearly.

Transit Operators

  • Automated interior stop announcements: Transit operators who participated in the demonstration debriefing reacted positively to this function, noting it allowed transit operators to focus on driving.
  • Automated exterior route and destination announcements: Participants had mixed reactions to the automated exterior route and destination announcements. Some operators liked the announcements, as they saved operators the task of shouting the route number out the front door to waiting customers. Other operators recommended that the announcements only play once at a bus zone, regardless of the number of times the doors were opened.
  • Automated exterior route destination sign changes: Transit operators who participated in the demonstration debriefing reacted very positively to this function, perceiving it as a timesaver for transit operators.
  • Automated public service announcements: Participants reacted positively to this function, describing it as useful, but difficult to access on the demonstration Transit Control Head installed above the operator's compartment for the short-term demonstration installation.
  • Schedule adherence and on-route status: Transit operator debriefing participants had a negative reaction to these functions, perceiving them as not useful. Participants noted determining the coach's schedule adherence and on-route status was their responsibility.

Vehicle Maintenance Staff

  • Vehicle Maintenance staff participating in the demonstration debriefing noted the generic canned reports provided by the Automated Vehicle Monitoring functions generally were not useful to VM staff as presented. VM staff however, saw great potential in the functions, if they were more closely tailored to meet user needs to:

- Collect information required by King County Metro VM staff, especially discrete input/output data. The demonstration Mobile TA tools and AVM web reports did not include input/output (I/O) data, which VM staff found more valuable than the data from the J1708 network, such as oil pressure, which are generally available through gauges or a laptop.

- Provide the ability to triage coaches needing repair as they return to the base according to their need for maintenance. While the demonstration equipment provided this capability, the function would also need to identify out of tolerance components, and include discrete I/O data.

- Report detailed AVM data within an hour and in a user-friendly format.

Technical Approaches

Good technical performance and potential, given a short-term effort

The technical performance assessments of the demonstration equipment conducted for this evaluation produced a range of results, understandable given the short duration of the demonstration. Most participating staff were impressed at how well the equipment performed, given the demonstration was conducted in advance of a full requirements development, procurement and acceptance testing process.

Significant findings related to the technical approaches employed by the demonstration equipment included:

Automatic Passenger Counters (APC):

In a comparison with passenger counts by onboard observers, the demonstration APC equipment performed well overall. The demonstration APC system met or exceeded 12 out of 18 current KC Metro APC performance criteria. APC staff anticipated the remaining specifications could be met if the supplier had been given time and approval to optimize the function.

Automated Vehicle Monitoring:

In a limited test conducted by vehicle maintenance staff, the AVM data correctly reported a disabled 35 mph switch and radiator fan control switch, and observed values for oil temperature, oil pressure, cooling temperature, and voltage.

Data Transmission to Transit Signal Priority (TSP) Equipment:

Schedule deviation and passenger load data were transmitted and read by the Transit Signal Priority system, demonstrating the real-time dynamic data from the onboard system could be transmitted to the TSP system.

Automated Vehicle Location (AVL):

When displayed on the King County Metro Transit GIS map, a small sample of demonstration onboard AVL data was well aligned with the coach's scheduled route, and the path taken in off-route operation.

Issues identified in the analysis included:

  • The demonstration onboard AVL system identified a small percentage of bus stops that were located incorrectly by King County Metro on the Transit GIS map.
  • Apparent problems in GPS signal reception on Third Avenue in downtown Seattle and in the Downtown Seattle Transit Tunnel did not impact the performance of the demonstration system in operation. However, the onboard data record did not include the final corrected GPS data available, which would be desirable in a system wide implementation.
  • The on-/off-route status indicator was triggered immediately by significant changes in the direction of coach travel, but gradual changes in direction were slow to indicate a change in on-route status. In addition, off-route operation on a street parallel and in close proximity to the coach's expected route did not trigger off-route status. The Smart Bus system had many system parameters that could have been optimized to improve performance had the supplier been given an opportunity, as would be expected in a system wide implementation. The demonstration system capitalized on frequent stops to improve the onboard AVL processing with GPS. Additional evaluation and testing may be required for King County Metro service with few stops, such as express or night service.

Issues Identified, Lessons Learned and Next Steps

The Smart Bus Demonstration Project highlighted business process issues and future bodies of work required for system wide implementation of the technology at King County Metro, including:

  • Announcement timing and on-route status parameters: The optimum settings of the performance parameters controlling the timing of the next stop announcements and the on-route status mechanism will need to be determined to provide the highest performance reliability across the KC Metro service area. Future decisions for system implementation at King County Metro include operational and policy impacts and transit operator training.
  • APC process change: The implementation of smart bus integrated APC equipment will result in changes to the current APC process, notably reduced data post-processing, and increased volumes of data. Along with integrated APC technical requirements development, a significant next step in the effort will be defining APC business process changes and staff roles in an onboard systems environment.
  • Data management process change: The demonstration highlighted significant future KC Metro efforts related to the data management process changes required for onboard systems implementation, including the data management process onboard the bus, the distribution of data from the onboard database to the user databases, and historical database design and maintenance issues.
  • Explore testing requirements, process for system acceptance: The evaluation technical assessments highlighted the need to explore methods for rigorous AVL, AVM and other onboard systems acceptance testing, including establishing performance criteria, level of effort, and methods for processing the large volumes of data that would be required.


Through their experiences with the demonstration project, King County Metro Transit staff were able to more clearly envision the benefits of the smart bus technology, including:

  • Enhancement to transit operator work environment: Most transit operators participating in the demonstration debriefing perceived the automated next stop announcements, automated route destination sign changes, and automated public service announcements as enhancements to their work environment, allowing them to focus on the operation of the vehicle and customer relations.
  • More reliable APC equipment, more streamlined data processing: APC project staff anticipate that implementation of technology similar to the demonstration APC units would provide a number of benefits to APC data processing including:
    • Fewer repairs on APC units: Infrared light beam technology is expected to be less prone to damage in the coach environment than the current mat-based units.
    • Easier repairs with new, modular APC equipment, less impact on data collection.
    • Less post-processing of data.
  • Enhancement to customer's riding experience: While the Smart Bus announcements and displays were designed primarily to benefit riders with disabilities and to meet federal ADA requirements, other riders also found the functions useful. The onboard survey results suggest a potential that other customers may perceive the functions as enhancements to their riding experience.
  • More efficient triaging of coaches needing repair: Vehicle Maintenance staff participating in the demonstration noted implementation of the Mobile TA Tools or similar function would allow them to identify coaches needing repair ("BO" coach) and park them were they can be easily accessed.
  • Accessible Vehicle Maintenance diagnostic data: Through their experience with the demonstration AVM functions, participating Vehicle Maintenance staff envisioned the potential benefits of an AVM system if tailored more closely to staff needs. Quick access to diagnostic AVM data would enable staff to:
    • Manage fleet availability more effectively by identifying which coaches can go back into service and when;
    • Manage staff work flow more effectively by identifying the expected duration of a repair job and staff availability to perform the work;
    • Provide more preventive maintenance by utilizing the time saved from more efficient repairs.

III. Conclusions

In summary, the Smart Bus Demonstration equipment performed well overall, given the short duration of the demonstration, conducted in advance of a formal requirements development effort.

The demonstration provided a valuable opportunity for:

  • identifying technical and business process issues and future bodies of work for the onboard systems effort;
  • incorporating transit rider, transit operator, vehicle maintenance, and technical staff feedback into the requirements development process;
  • identifying the benefits of the technology through users' hands-on experiences.
Updated: Sept. 2002