The high volume of commercial freight transport on German motorways makes it difficult for truck drivers to find safe parking places especially for longer rest periods during the night. Even though expansions have been made to satisfy the demand, overcrowding and dangerous situations still occur as a result of vehicles parking in the entrance and exit roads of rest areas. In addition to long-term extension measures, intelligent transportation systems (ITS) can also be deployed in the short and medium terms in order to achieve an improved distribution of the demand and an increase in the capacity of rest areas. The German Federal Highway Research Institute (BASt) developed a new control procedure, called 'Intelligent Controlled Compact Parking' (hereafter referred to as 'Compact Parking' for short), to achieve that trucks are parking in a compact way, side by side without driving lanes between trucks. Compact Parking offers a wide range of departure times on variable message signs. Drivers ought to use the parking row where their intended departure time is offered. To develop and test a possible algorithm for compact parking a user interface has been programmed, which maps the calculated departure times and a (theoretical) occupancy of the parking rows. The graphic user interface can be used to place individual vehicles on a virtual rest area at one click. In this way, certain functions and variants of an algorithmic implementation have been tested. The algorithm of Compact Parking does not require the drivers to announce their actual departure times. Instead, the calculation of the contents of the variable message signs is based on an algorithm using knowledge about typical truck driver demand patterns (according to legal rest time regulations). So, for example, in the evening a lot of arriving drivers intend to park for about 9 to 11 hours. During operations the control system offers the departure times that are demanded for as long as possible. For this purpose the current departure times of fully occupied rows are shown on variable message signs of other neighbouring empty rows. Important structural and operational constraints for practical implementation are given to avoid incorrectly parked vehicles. This includes the provision of information which departure times (in which parking row) are still available, and occupancy plans, which illustrate when trucks intend to leave the rest area. The essay describes the newly developed control procedure 'Compact Parking'. (Author/publisher)
Abstract