In this situation, a modern elevator is being built to move people and other objects from one floor to another in the Duke Centennial Hall.
Step 2: The alternatives to be compared are the configuration based on the height of the structure, the hoist function and the form of the building.
Building height accommodating the plan would be based on the height of the Duke Centennial Hall, which is a mid-rise building that can be fitted with geared traction elevators.
The goal is to use the technologies of speed and comfort. This has the advantage of productivity and a reduction in the use of a lot of electricity. Hoisting mechanism the design can be based on the hoist mechanism, which could be either hydraulic , traction, climbing, or pneumatic.
The focus is to use the technology of energy conservation. This minimizes the utilized energy but has the limitation of denying users efficiency and effectiveness level
Building type – the design will focus on ensuring that the elevator has the potential of meeting the needs of the commercial building where education takes place. As such, it has to focus on weight of the students and tutors and the items, which these people carry as they move in the classrooms and research laboratories.
The focus is to use the technology of available space. The benefit is to economize on the building space but there is a limitation of using a lot of energy.
Step 3: The criteria for the design includes safety, ease of use, cost, durability, usable space,
attractiveness and accessibility. These are considered as the main factors, which influence the attainment of success in the usability of the new elevator at Duke Centennial Hall.
Safety – the perceived safety of the new elevator system to the users. This includes the
safety of the system to the entire building and its occupants.
Ease of use – the ease for the use to utilize the new elevator system. Such includes how the users will be able to interact with the new system and find comfort in using it to serve their purpose.
Cost – the overall cost of the new system including the materials and labor
Durability – the long-lasting of the system for its use in the current status without deterioration or the requirement for repairs
Usable space – the occupancy level of the system to maximize on its performance in the building
Attractiveness – what are the physical features and ornamental design for the system?
Accessibility – how easily can the users make use of the new elevator system?
Step 4: It is assumed that all the criteria is important at first. However, safety, cost, and usable
space is ranked as the most important for this design. The weights as reflected in the figure 1 below are based on relativity of 100 percent total.
Step 5: The alternatives are evaluated and compared to a datum where 0 refers to “the same”, 1
refers to “better than,” and -1 refers to “worse than.”
Step 6: After doing a quick computation of the satisfaction, the unweighted results do not give a
clear direction of what needs to be done or the best configuration. However, the weighted computation gives results, which indicates that building height is the best alternative for the design of the new elevator for Duke Centennial Hall. Hence, building height should now be used as the datum for the design work.
Issue: New elevator for Duke Centennial Hall Baseline Building height Hoisting mechanism Building type
Safety 20 Datum 1 0 0
Ease of use 15 0 1 0
Cost 20 1 1 -1
Durability 10 1 0 0
Usable space 20 0 1 1
Attractiveness 5 0 0 0
Accessibility 10 0 -1 1
Total 3 2 1
Weighted total 50 45 10
Figure 1: Decision matrix for a new elevator for Duke Centennial Hall
Ullman, David. The mechanical design process.4th Edition. The McGraw-Hill Companies, 2010.