1. Introduction

EU's Fourth Framework for 1994 to 1998 has been completed. The CHAUFFEUR Project which was part of this development phase was also completed with a report and demonstration held on December 14 and 15 to EU officials, and demonstration for the general public is scheduled to be held in March, 1999, at Brenner Pass in Austria. Prior to this public demo, a special demo was arranged by Daimler Chrysler for AHSRA.
Venue: Daimler Chrysler testing grounds (Papenburg)
Date: December 17, 1998 (Thurs.)

2. Background and Outline of the CHAUFFEUR Project

The CHAUFFEUR Project was organized as part of the Fourth Framework for improvement in distribution efficiency, environmental improvement, and safety by the Telematics Application Programme of the European Commission in 1996.
The project is an electronically linked platooning project developed under the initiative of Daimler-Chrysler (along with Fiat, IVECO, Bosch, CRL, WABCO, ZF, etc.). The platooning demonstration was that of the "Tow Bar System" in which one vehicle follows another manned vehicle.

3. Description of Demonstration

The "Tow Bar" demo had ended until now with confirmation of control performance employing van-type vehicles at the 1998 AVG Holland demo. This time, it was a demonstration on full-scale distribution efficiency and safety employing heavy duty tractors with trailers respectively.

3-1 Specifications

(1) Vehicle
(a) ACTROS 1853 tractor (gross weight of 18 tons; engine with 530hp) and trailer (GCW(gross combination weight) 40-ton class, with retarder) (The test was conducted with empty trailers.)
(b) Number of axes: 2 for tractor and 3 for trailer
(c) Braking system: Electronic braking system (full-air drum brake)
(d) Steering system: Electronic hydraulic booster
(e) Transmission system: Automatic 16-step forward transmission (2-step front part planetary gear x 4 steps x 2-step rear part planetary gear)

(2) Lead vehicle platooning graphics processing
(a) Infrared lamp of lead vehicle (6 commercially available lamps)
6 placed in large circle on back door of the trailer. 8 holes bored for lamp installation. (See Photo 1)
(b) Graphic mark photography cameras of the trailing vehicle (2 CCD cameras) (See Photo 2)
One for wide-angle view and other for telescopic view.

(3) Monitor inside cabin
Lead vehicle: Speed, acceleration speed, etc., of trailing vehicle.
Trailing vehicle: Infrared lamps, speed and acceleration speed, headway, transmission gear position, etc., of lead vehicle.2.5GHz used for vehicle-to-vehicle communication (5.8GHz scheduled). Relative distance monitored with millimeter-wave (76GHz) radar as supplementary duplicate system for infrared lamp.

(4) Control unit
(a) Power PC
(b) Graphics processing device
(c) Signal conditioner
(d) Controller unit

3-2 Condition of the Course

Two vehicles are positioned on the skid pad installed inside the oval circuit (12km per lap) and started from this point.
The road surface was slightly wet, and snow remained at the side of the course (See Photo 3)

3-3 Demo Cruising

"Tow Bar" in which two vehicles were linked electronically cruised at speed of 0 to 85 km/h, keeping bumper-to-bumper clearance of 10 to 17m and showing the trailing vehicle following in response to lane change, deceleration, acceleration, stop, and start of the lead vehicle.
The trailing vehicle showed no problem in automatic platooning to a manned vehicle, even in strong sunlight too brilliant for human eyes. However, control of the trailing vehicle switched to manual at intersection, where the infrared mark of the lead vehicle disappeared totally from frontal view.

4. View of Control

The trailing vehicle (automated driving but with driver on board) trailed the lead vehicle (controlled by a driver) automatically by detecting bumper-to-bumper clearance and six degrees of freedom, including lateral shift, speed, acceleration, etc., of the lead vehicle are communicated from vehicle to vehicle for faster control response. In view of variance in vehicle-to-vehicle performance and communication delay, bumper-to-bumper clearance has been kept at 10+0.3V (V is vehicle speed in m/s) meters. This is constant value regardless of road surface condition (moisture, dryness, snowfall, or rainfall). The target for the future in 5m, and the influence of difference by vehicle performance is expected to be compensated by vehicle-to-vehicle communication.

5. Daimler-Chrysler Policy on CHAUFFEUR Applications

(1) Vehicle
Due to the fact that CHAUFFEUR use on small commercial vehicles has little benefit, it is being considered chiefly for heavy duty commercial vehicles.
Daimler-Chrysler believes that, even if the trailing vehicles are manned, this will have the advantage to cutting down driver burden drastically.

(2) Cost performance
Details of CHAUFFEUR evaluation by the University of Cologne are not available, but cost-benefit ratio reportedly quadrupled in terms of accident reduction, driver cost, fuel economy, greenhouse effect, etc.

6. Future CHAUFFEUR Plan

Longitudinal control is expected to be introduced in 1998, and lateral control in 2005. "CHAUFFEUR Assistant System" in which the second vehicle will have a driver on board but with dramatically less driving load, is scheduled to be completed in 2010 (give or take 5 years). The company is planning to complete the "Tow Bar" consisting of manned lead vehicle and unmanned or manned but less driver load for the trailing vehicles, in 2015, "Platooning" of a multiple number of vehicles led by a manned lead vehicle in 2020, and "Automated Platooning" of fully-unmanned cruising by year 20XX.
The study into platooning of a multiple number of vehicles requires examination of social acceptance and infrastructure development. System evaluation will be conducted through traffic flow simulation in the future. The CHAUFFEUR system will be added to the Fifth Frame starting next year as CHAUFFEUR II.

7. Acknowledgements

The demo provided much to learn for AHSRA in studying into service for greater distribution efficiency. Based in the knowledge and experience, a study will be made into greater service refinement and system planning. In addition, technical exchange with Daimler-Chrysler will be bolstered in the future, for study into methods in system review and evaluation items, as well as into practical applications.
Lastly, we must acknowledge thanks to Mr. Metzler, Mr. Schulze, Professor Vogel, Dr. May and many others at Daimler-Chrysler for sparing time from their hectic pre-Christmas schedule and arranging this demo for us.