TRL was asked to produce guidelines which specify what an ergonomically acceptable OBU would be like. This report considers the user requirements of the OBU. The user requirements produced fell into three categories: general user requirements, user requirements for tags (to be used with off-board accounts), and user requirements for card based OBUs. Within the general user requirements, the size, case, method of mounting the OBU, ability to remove the OBU, power supply, use of a status indicator, method for activating the OBU, and the colour of light used were all considered. With regards to tags (used with off-board accounts) informing users of transactions, the use of display screens, and the position of the tag were all dealt with. The specific user requirements for card based OBUs were then considered, the topics explored being: the type of card used, the positioning of the OBU, the card slot, incorrect card insertion, the use of a spare card holder, the types of information to be displayed and the best methods for doing this, changing cards, auditory warnings, and controls. Recommendations were made regarding the above user requirements. These were supplemented with examples that illustrate how the user requirements could be put into practice. (A) (This report is also included on the TRL CD-ROM entitled "Research on road user charging 1995-1998"). For the covering abstract see IRRD 491340 or C 12559 CD-ROM.
Abstract