USDOT Seeking Proposals for Testing of Heavy Truck Electronically-Controlled Braking 
IVsource.net
15 August 2002

On August 12, the US Department of Transportation issued a Request for Proposals to conduct a field operational test (FOT) of heavy trucks equipped with electronically-controlled braking systems (ECBS).  IVsource provides a quick-look overview of the project envisioned by the government, as well as requirements for proposers.

On August 12, the US Department of Transportation issued a Request for Proposals (RFP) to conduct a field operational test (FOT) of heavy trucks equipped with electronically-controlled braking systems (ECBS).  The solicitation comes from the Federal Highway Administration, but technical program management is expected to be assigned to the Federal Motor Carrier Safety Administration.  Applications are due October 16, 2002.

This initiative will form a new component of the government’s Intelligent Vehicle Initiative.  The solicitation notes that while poorly performing and/or out-of-adjustment brakes are a contributing factor in some crashes, in many other cases the brakes are working just fine and it is enhanced braking performance that is the key in avoiding or mitigating crash situations.  Additionally, since brake systems represent the second highest vehicle maintenance cost item for most fleet operators (next to tire maintenance costs), brake system enhancements are seen as a fertile area for research.  

The ideal ECBS system will improve braking efficiency, increase reliability,  and reduce overall maintenance and operational costs due to decreased wear.

The purpose of the FOT is to achieve an improved understanding of the broad safety impacts of ECBS, and in particular to capture the positive safety benefits of these systems in an over-the-road, 'revenue-generating' environment.  All systems field tested as part of this program will be evaluated in terms of ECBS performance, reliability, durability, and maintainability.  In addition, a general safety benefits evaluation will be performed for those systems with advanced brake safety system components (high speed communications, “balanced braking” components, etc.).

According to the solicitation, the government views ECBS as an enabling technology that can provide shorter stopping distances, improved dynamic brake force distribution, and improved combination vehicle brake balance.  Combined with additional sensors such as lateral accelerometers and yaw rate sensing, Enhanced Stability Programs (ESP) could be developed which leverage the precise wheel-by-wheel braking control offered by Electronically Controlled Braking System.  Together, Electronically Controlled Braking Systems and Enhanced Stability Programs (known collectively as "intelligent braking") could be used to offer improved control to commercial vehicle drivers, particularly under distressed or “panic” maneuvers.  Furthermore, when combined with lining wear sensors, Electronically Controlled Braking Systems offers the potential for improved self-diagnosis, continuous brake monitoring, and possibly reduced overall brake system maintenance costs.

ECBS have been around since the early 1990's and such systems are routinely sold on heavy trucks in Europe. The adoption process was facilitated by a standard developed by European manufacturers for high-speed network communications between tractor and trailer (ISO 11992).

The government RFP document lists several reasons that may account for the fact that ECBS for heavy-duty trucks have not gained commercial acceptance in the North American market.  Key factors include:

• Electronically Controlled Braking Systems are more expensive than Anti-lock Brake Systems (ABS).
• The performance benefits of Electronically Controlled Braking System alone (i.e., not in combination with disk brakes) have not been clearly documented in terms of stopping distance and safety improvements.
• The durability, reliability and maintainability of Electronically Controlled Braking Systems have not been verified for North American applications and operating environments.
• Implementation of ECBS is generally understood to be an “enabler” of braking control strategies that can offer major improvements in brake performance; but as a stand-alone system, benefits may be moderate and not perceived as a “good value” by some fleet operators.
• Lack of a standard high-speed network connection between tractor and trailer limits development of an “optimal” ECBS control strategy for the combination vehicle, which therefore limits the relative benefits of EBCS compared to standard ABS.
• More so than in the European market, tractors and trailers of varying age, design and even ownership must be compatible with one another.  This creates a “chicken and egg” challenge since maximum benefits of ECBS cannot be realized unless both tractor and trailer are equipped with the new technology.  Fleet operators are reluctant to “go first” with regard to purchasing the new technology.  Additionally, it is imperative that the tractor EBCS be compatible with the trailer EBCS, as well as have backward compatibility with ABS.

Key Objectives of the FOT

As listed by the government solicitation, the FOT objectives are:

1. To evaluate the overall safety of Electronically Controlled Braking Systems (ECBS) in terms of performance, reliability, maintainability, and durability in a variety of real-world environments by collecting real-time braking event data and collecting additional information from brake technicians and drivers.

2. To evaluate the safety benefits of ECBS in terms of mitigating near crash or degraded situations for systems with advanced brake safety system components. 

3. To identify issues that affects the suitability of ECBS technology in an over-the-road, revenue-generating environment by documenting any problems or fault codes with the systems, as well as the frequency and circumstances of ECBS failures that would result in braking control being “switched” to the backup pneumatic system.

4. To assess the maintainability of ECBS relative to scheduled and unscheduled maintenance requirements, mechanic skill level impacts, and/or ability to diagnose and resolve problems.

5. To document driver information/experiences resulting from ECBS use, focusing on driver acceptance, feedback related to system use, and behavior change.

6. Evaluate the compatibility of tractor and trailer ECBS from different vendors with conventional Anti-lock Brake Systems (ABS).

7. To evaluate the overall performance and reliability of “optimized” ECBS technology for tractor/trailer combinations where both tractor and trailer have ECBS with advanced safety features such as a high-speed network.

Tasks Defined

The government document lists the following required tasks:

Task 1 – Generate Field Operational Test Plan with Government Approval

Task 2 – Assemble Test Vehicles with ECBS

Task 3 – Conduct ECBS and Data Acquisition System (DAS) Check Out Testing

Task 4 – Conduct Field Operational Test

The government is particularly focused on ensuring a robust design for the data acquisition system.  This undoubtedly stems from challenges encountered during the current round of heavy-truck IVI field tests, in which acquisition of reliable, useful data has proven to be a major headache.  The solicitation stipulates that the refined field test plan “shall include a detailed data acquisition system design outlining the physical design, method for collecting data from the Electronically Controlled Braking System (ECBS) Electronic Control Unit (ECU) and the other vehicle sensors, algorithms used to collect triggered data, data storage type and capacity, and the predicted system reliability.  In addition, the final field test plan should outline the procedures for data acquisition system installation and validation, and describe the Team’s strategy for harvesting data from the on-board data acquisition system for distribution to the Independent Evaluator.”

Knowing that these FOTs can come in many shapes and sizes, USDOT has opted to define three templates for the type of tests that will be conducted.  Proposers are free to define their test based on any one of these.

Template 1 is focused on Severe Duty applications, such as Class 7 or 8 refuse haulers, Class 7 or 8 dump trucks, pick up and delivery vehicles, and city transit buses.  Minimum test fleet requirements are ten (10) vehicles operating for a period of twelve (12) months.

Template 2 is focused on “mixed” tractor-trailer combinations, to evaluate the compatibility and performance of tractors and trailers that are equipped with ECBS from different vendors.  The Government says they recognize that if/when ECBS technology becomes commonplace there will be a significant transition period during which tractors equipped with ECBS will be paired with older trailers equipped with or without Anti-lock Brake System (ABS) brakes.  The reverse situation may also occur, that is, ECBS trailers may be paired with tractors equipped with or without ABS.  Also, there is the potential for tractors equipped with ECBS from one vendor to be paired with trailers equipped with ECBS from a different vendor.  The purpose of the Template 2 FOT is to evaluate the compatibility, reliability and performance of these various combinations.  Template 2 applicants are required to equip a minimum of 10 tractors with ECBS from one supplier, and 10 trailers with ECBS from a different supplier.  The modified tractors and trailers must then be placed in an operating environment that will allow for ECBS tractors and trailers to be paired during revenue service, but also allow for the ECBS vehicles to be paired with Non-Electronically Controlled Braking System (Non-ECBS) based equipment.  The test vehicles are to be operated for a minimum period of 12 months.

Template 3 focuses on an “optimized” tractor-trailer, with the objective being to evaluate combination vehicles where both tractor and trailer are equipped with optimized and/or advanced ECBS technology.  Proposed systems must incorporate one or more advanced brake system safety component to improve the vehicle’s crash avoidance capability.  Examples given of advanced braking safety system components include an Adaptive Cruise Control Systems (which utilize the EBCS system to control vehicle speed), an Electronic Stability Program, and a Balanced Braking Control Program.  Further, the braking systems on the tractor and trailer must be linked via a high-speed data connection bus (e.g., meeting J1939, or ISO 11992 standards).  Applicants are required to equip a minimum of 10 tractors and trailers with ECBS technology and operate the vehicles in “married pair” combinations.   A control fleet (minimum of 10 vehicles) will be required so that ECBS vehicle performance can be compared to that of non-ECBS vehicles.   A twelve (12)-month period is envisioned during which an enhanced data collection effort would be used to evaluate the potential safety benefits of the ECBS.

The government seeks partners for a cooperative agreement to conduct the FOT.  The solicitation states that the total project will last three years, and cost-sharing is “anticipated.”  It is also possible that multiple awards will be made, depending on the nature and quality of the proposals (and available budget).

The government is looking for a team that consists of (at minimum) a manufacturer of heavy-duty vehicles, a manufacturer/supplier of braking control systems for like vehicles, and a fleet operator (or Host Site operator).

A Pre-Proposal Conference is set for 10 am to 12 noon on September 10, 2002 at USDOT, 400 7^th Street SW, Room 7236, Washington DC. 

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For More Information ...

... the solicitation is number DTFH61-02-X-00096 and can be found on the web at www.eps.gov/EPSData/DOT/Synopses/30/DTFH61-02-X-00096/DTFH61-02-X-00096z-08-12-02.rtf.

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