Group 22 - Tecumseh Engine
- Introduction to Mechanical Engineering Practice (MAE277) is a course designed to give students the opportunity to apply and understand the basics of engineering. Throughout the semester students learn the principles of Mechanical Engineering such as the design process, types of manufacturing and important steps of problem analysis. The students are then able to apply this knowledge to a group project based around the reverse engineering of a mechanical system.
- During the project each group was able to pick a mechanical system to disassemble, analyze and reassemble. It is divided into five seperate checkpoints called "Gates" that focus on different aspects of the project as described below. In order to complete each gate the group must do the necessary research for each topic discussed in the assignment to relate to their product. The group then provides this knowledge in an orderly documentation on the wiki website including tables, figures and links for the convenience of the user.
- The project began with the selection of a mechanical system for each group to dissect and learn about. Group names were posted on the website and the students were given the responsibility of getting the product proposal together. During this stage of the project our group all met in Capen Hall for the first time to discuss the roles of each member and the assignment at hand. Our group was assigned with a small Tecumseh TVS120 5hp internal combustion engine. Our group used the lack of knowledge with engines and little Wikipedia formatting experience as motivation to take this opportunity to learn about something we were all interested in. At this point in the project the group decided splitting up work and collaborating at the due date would be the most efficient way to get our assignments done.
- During the initial assessment and dissection of our product our group learned a lot about the functionality as well as the parts of the engine. The group was able to split the parts into two separate categories (external and internal parts) to create a plan for dissection. Each part was researched for its function and orientation inside the engine as this would make it easier to keep track during the disassembly process. The group also researched the types of energy transfers that occur during the operation of the engine, from the initial human and chemical energy to the final rotational mechanical energy. Throughout this stage of the project the group began to notice the members of the group that are dedicated to each step of the project and the members that might be problematic in the future. Meetings took place and Capen Hall and were on a regular basis as communication was going to be the most important factor for the success of our group.
- After the initial assessment was complete the group was able to move on to the dissection process. During this part of the project the group began taking apart the engine while documenting the whole process. This is where the group began having problems with two of the members as they began to contribute less and less to the group. The majority of the group however was able to complete the dissection of the engine. The dissection of the engine gave the group physical experience to apply their research to. Also the group began to improve their wiki formatting, as only one of the members had previous experience. Proper documentation included pictures and descriptions of each part as it was disassembled in the lab.
- As the semester went on each of the group members began to realize the technical communication issues that were extremely apparent within the group. Both group members were confronted about their lack of effort at the next group meeting and were given another chance to complete future assignments with more focus. With this in mind the group began to analyze each component that was taken from the engine. This was the most part of the project as the group not only needed to understand each component’s functionality and individual component interactions but the group also was asked to find ways of improving the system. Improvements included a direct overhead valve system, automotive style piston rings, improved filters and a reduction of weight. The group also learned about the manufacturing of one of the most important parts of the engine; the piston. The group was able to apply both the manufacturing knowledge learned in class about each of the four major processes as well as the influence of the four factors on product design.
- The semester came to a close and as the project began to wind down the group experienced slight hostility to some of the members. The group manager tried extremely hard to gather the whole group for each meeting but was not able to fit everyone’s schedule. Two of the members continued to contribute nothing beneficial for submission and the other three began to realize how little time was left and decided to take charge. Each assignment was then distributed to each member based on the effort of previous assignments. This meant that the three members that were still dedicated to the project would get most of the work done in a mannerly fashion. This new style of work distribution was reflected when it came to gate four. The reassembly process was extremely simple as the group’s knowledge of each component and the accessibility of necessary tools allowed for a quick and efficient procedure. The documenting process was similar to that of gate two (the disassembly process) as the group used necessary pictures and information to illustrate the proper techniques for reassembly of the engine.
- Overall the group found it extremely hard to work as a team and tried their best to motivate others to complete each assignment as detailed as possible. The most significant factor that led to our group’s downfall during assignments was the lack of communication. Poor group meeting attendance led to late submissions and insufficient work. This was resolved by assigning work earlier and enforcing a cross reference of each members work before submission. Although the group faced many disadvantages (lack of knowledge about engines, lack of wiki formatting experience, lack of group availability/cooperation, etc.) they pulled together to complete each assignment and overcome each challenge to submit and complete each assignment received.
The Tecumseh 5hp Engine (See Figure 1)
- Internal Combustion
- One Cylinder
- Four Stroke (Two Valves)
- Gasoline Powered
Matthew Whitman, Darroch Moorhead:
The project consists of five gates that describe each step of the processes of planning, dissection, analysis and reassembly on the engine as described below:
Gate 1: Project Planning
- Main Article: Gate 1: Project Planning
The purpose of this initial gate was to lay the ground work for the rest of the project. We analyzed our group's initial strengths and weaknesses, developed a tentative meeting schedule, and planned out the dissection of our product. Our preliminary dissection plan was completed by researching the manufacturer of our product and products of a similar size and function.
Gate 2: Product Dissection
- Main Article: Gate 2: Product Dissection
As our group began to become a team, we set off to reverse engineer our product. Most of the group members gathered in lab to finally see the inner workings of our product. This gate shows the results of our dissection along with review of the group's cohesiveness.
Gate 3: Product Analysis
- Main Article: Gate 3: Product Analysis
With the engine completely dissected, the group set off to gain a better understanding of our product. Through research of engines in general, we were able to see the subsystems and overall flow of the engine. The results of our work are shown in Gate 3.
Gate 4: Product Explanation
- Main Article: Gate 4: Product Description
The main purpose of Gate 4 was to reassemble the product. The group learned a lot more from assembling the product than from disassembling it as we gained a better understanding of engines. Smaller systems and components were investigated and parts were researched and replaced. Individual group members took charge at this point as will be discussed in the Cause for Corrective Action section.