Concept Design:

From the research, four concepts were considered for the frame and seat of our Human Powered Vehicles. The first concept (Shown in figure 6 below) uses a simple main frame structure with a cross member to attach the front two wheels. 

 

 

 

 

 

Second Concept design (Shown in figure 7) keeps the similar main frame structure but eliminates the cross member. The kingpin cylinders are mounted on a shell attachment extension tube that follows the contour of the shell. 

 

 

 

 

 

 

 

The third concept design uses a similar main frame as concept 1 and 2 and uses the cross member from concept 1. This design however uses the cross members as an attachment point for the seat. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The forth and the final concept (shown in figure 9) is developed by taking the third concept and eliminating the frame adjustment and introducing the seat adjustment. The seat is connected to an adjustable bracket which can move toward or away from the crank set.  

 

 

 

 

 

 

 

 

 

 

Using scoring matrix shown below, all four concept designs were compared with the project requirements. A multiplying factor (1-5) is used to distinguish important design perimeters.

Using scoring matrix shown below (Table 2), all four concept designs were compared with the project requirements. Concept 2 was eliminated because the design failed to provide clearance for the front wheel attachment. Concept 1 was also eliminated because aftermarket seats are very heavy or very expensive. Thus, only concept 3 and 4 are compared using the matrix.  A multiplying factor (1-5) is used for each design parameter to distinguish important design perimeters. Total of four design parameter are for scoring.

 

From the table above, it we can see that concept 4 follows the requirements better than concept 3. Thus, concept 4 is chooses for the final design for this project.  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 10, shows a detail description of the design of the frame and seat assembly with their parts labeled. All the components will be made individually and assembled them after. Maine Frame assembly has five major components shown in Figure 10 (A) and detail description of the seat assembly is shown in figure 10 (B).