COMOL: Computer-aided operations and management of the lift

Abstract

A comprehensive vehicle scheduling system has been developed for the City of El Paso's LIFT transportation service. The LIFT transportation service is a bus service for the physically handicapped and the elderly and it provides door-to-door service. COMOL (Computerized Operation and Management of the LIFT) is a generalized database management system developed to manage operations similar to the operations at the LIFT. It has a modular design and consists of six interlinked modules. Each module has been developed to handle a particular subset of the entire operation. For example the Trip Request module was designed taking into consideration that the dispatcher can take in all types of trip requests within this module. All different options needed for editing of trip requests are available in this module. However, data flow between the modules ensures that this information is available to the dispatcher in the Vehicle Scheduling module. The system has been designed so that any specialized needs can be included as a separate module. The databases were carefully designed to optimize access time and the passenger identification number was chosen as the link to provide a ‘dataflow chain’ between the different databases. Productivity gains are defined in terms of number of trip requests completed per hour and the amount of additional time available to the operators to carry out scheduling. A preliminary time study carried out showed that the time required to take in a trip request using the current manual system was 135 seconds as opposed to 20 seconds required by COMOL.