Create a preliminary version of the design class diagram (first-cut design class diagram) for the Car Sharing IS. This requires that you (a) elaborate class attributes, and (b) add navigation visibility arrows

1. When wanting to use a car share vehicle, members contact the scheduling system through one of several interfaces (telephone or internet), and identify themselves. Their preferences (preferred vehicle type and location) are then loaded, and the member is asked to confirm the preferences for this reservation, and given the option to change the preferences permanently, or for this reservation session only.

1. The member is prompted for the desired date, time, and duration of vehicle use. There are no restrictions on scheduling vehicles except that vehicles may only be reserved for 90 days in advance.
2. If a preferred vehicle is not available at the desired time and location, alternative vehicle types and locations are offered. Other car share locations may be nearly as convenient and a different start time may be acceptable to the member. Typically, the closest location is within a five-minute walk.
3. When a reservation is successfully completed, it is recorded and an email confirmation is generated and sent to the member. (For telephone reservations the clerk reminds the member of the details).
4. A member may make any number of reservations in a given Web or telephone reservations session.

6. Once at the car, the member places the SmartCard above the detector field on the windshield. The on-board computer verifies first the user card, then the reservation and unlocks the car doors. As an added security measure, once in the car, the member is prompted to enter a personal identification number (PIN code) to access the cars ignition key which is placed in an electronically controlled holder in the glove compartment. During your trip the key is used to lock the car as usual.

7. Members are responsible for fueling. If, while using a vehicle, the fuel goes below one-quarter tank, the member is expected to re-fule. A fleet gas credit card is placed in each vehicle. These cards are restricted for fuel purchases only, and require that a vehicle number, odometer reading, and PIN be entered.

8. Other, unforeseen expenses incurred during a trip are paid by the member who then files an expense claim for reimbursement. If approved, the members account is credited.
9. When returning the vehicle, the ignition key is put back in the holder in the glove compartment. The on-board computer displays the trip data and automatically sends it to the central office. The member locks the car with the SmartCard.
10. Combining reservation and trip data, the billing software generates an itemized charge that is added to the members account.