9/14 - 9/21

This was the first week that the group split up design tasks. The main portions that need to be worked out are the joint for the bar that the suspension and propulsion connect to, and the linkages for steering. These two tasks were split between group members to work on solo, and to come together the following week to access progress. The calculations for the position analysis of the linkages is needed in order to size the motors that will be used to actuate the steering mechanism. The calculation are planned to be done in excel as to be fluid to change. A big unknown is location of the actuators. As of right now it is difficult to say where the will fit. Placement of the motors will make a huge impact on the design, and so we are currently trying to get a solid design of the bogie structure with placement of wheels, and cross members so that we know what we are working with in terms of placement. The upright structures are being redesign in order to place another wheel below the rails. This new design hopes to eliminate the issue of binding that the bogie experienced last year. Slight changes in wheel positions will also help. This week we plan on working together to develop the characteristic equation to describe the position, motion, and forces acting on the steering system. We also will continue working on the bogie structure. Preliminary hand calculations have been done to size the the joint according to the payload weight. The calculations indicated that a 0.25" diameter bolt will sufficient hold the load of 800 LB we spec'ed, however we are planning on using one somewhat large to take in account impulse force and fatigue that could occur and cause failure.