9/21-9/28

During this week, we continued working on our design and calculations of the steering and the sizing of some bolts considering the specifications given by previous semesters. Our group also focused on arranging together a presentation which will take place during this week. The presentation will emphasize the progress and the future scope to complete our design. In this week, recollecting data and and understanding how we wanted to presented towards the audience was critical in order for the rest of the sub-teams to understand the route we will be taking and how exactly it will influence each component being designed by them. The kinematic calculations for the steering were typed in order to avoid any confusion and also to avoid any mistakes when other teams revise the steps followed. After the kinematics, the force calculations will be next as we finalize the specifications and final designs to our project. Constructive criticism is always welcomed from any of our peers as it may lead to realize mistakes or it may also give root to new ideas. Also, some changes were made to the bogie 3D model with our new ideas considering the fails experienced by previous teams. The discussions on the new ideas we planned to implement in our design were implemented to show preliminary view to our way of thinking and what ultimately will become the new system. Below, pictures of the calculations and the design at this moment in the semester.

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.

Week 2

During this week, our main objective was to acquired as much data as possible and identify the issues with their respective solution. We begin by reading the previous summer team report to identify more accurately on what the main problems were present. During our research, we identify that the bogie did not fully functioned during previous test. We identify that the main problem was the constriction of the bogie. It is constrained in such matter that it does not fully travel across the track successfully. In our preliminary attempt to begin working in the project at hand, we begin by brainstorming and ultimately sketching as many ideas as possible which will be helpful in the design of our system. We also deduced that in order for our project to be successful, our sub-team requires to be in full contact with the rest of the sub-teams thus a fully Google Docs folder was created which will contain all the documents related to our project. Although all sub-teams may be working on different parts, our contribution will come together in the end, therefore full communication is of upmost importance. We began by introducing one another and exchanging information to fully create an environment of great communication and team work. Our project team is fully communicating in the lab as well as outside of school grounds. Our main objective for this upcoming week will be to further discuss our next course of action, fully understand the changes and design choices, keep communicating with our fellow team mates and ultimately begin the design analysis.

Week 1 Team Post

• Team members, with brief listing of pertinent skills
• Michael Kemp
• CAD Design, Assembly manipulation, machining (milling/lathe/waterjet), welding, integration, etc.
• Martin Chavez
• 3D printing, CAD

• Jorge Soto
• CAD Design, Assembly, Machining(beginner)

• Team members contact information
• Michael Kemp
• Telephone: (559) 577- 5365
• Email: Michael.Kemp@SJSU.edu

• Jorge Soto
• Telephone: (209) 292-1113
• Email: jorgeLsoto7@gmail.com

• Martin Chavez
• Cell: (510) 684-4809
• Email: martinchvz@att.net

• Team member responsibilities within the team (who will do what) -may change throughout the semesters
• Michael Kemp
• Manufacturing
• CAD Design and Drawings
• FEA

• Jorge Soto
• Modeling and CAD design
• Assembly
• Manufacturing

• Martin Chavez
• Sketches
• CAD

• Proposal narrative (verbal description of what is proposed to be accomplished, which includes design requirements and deliverables)
• Over all Bogie Changes
• Utilize 4130 steel tubing and sheets rather than A513/A36 in order to reduce weight while maintaining rigidity.
• Simplify design from previous and shorten all possible members to reduce weight and reduce risk of long term beam buckling due to large slenderness ratio.
• Attempt to integrate all subsystems in a manner that minimizes the volume envelope of the bogie design and reduces risk of interference and catching of members  
• Steering
• Shorten wheel mounts
• Use 2 linear actuator in order to shorten the linkages
• Look into removing lowe second failsafe wheels

Failsafe

• One wheel on each side instead of two in order to not overconstrain the system
• during turns
• Between bogies
• Add 2 DOF flexibility between bogies utilizing a drivetrain linkage design

• Sketches or drawings

• Critical Path Schedule using   https://gantter.com/   (Gantt chart website) -copy shareale link / screenshot of gantt chart in team blog.
• Budget (preliminary estimate of the cash and VIK – Value-In-Kind – needed to deliver what is being proposed)   Give an ESTIMATED RANGE for this.

Cost of materials will increase if the material is switched from Structure steel to Chromoly steel. A range from $600 - 1000 for the structure is currently projected, however it is hard to currently determine as new component and configurations have not be determined.