Shape Memory Alloy Valve Project

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					Cynthia Eppes                                                             E3 Final Report
Westside High School – Houston ISD                                     November 26, 2008
                              Shape Memory Alloy Valve Project

       Working with the Westside Engineering and Geosciences Academy (WEGA) teaching

team we introduced the topic of Shape Memory Alloys and the Design/ Problem Solving Process.

Shape Memory Alloys is an alloy that "remembers" its shape, and can be returned to that shape

after being deformed, by applying heat to the alloy. When the shape memory effect is correctly

harnessed, this material becomes a lightweight, solid-state alternative to conventional actuators

such as hydraulic, pneumatic, and motor-based systems. The Design Process is the process of

devising a system, component or process to meet desired needs. It is a decision-making process, in

which the basic sciences, mathematics, and engineering sciences are applied to convert resources

to meet a stated objective.

       The students were introduced to the Design Process over a three-week period of time. The

basic concepts were presented to the students via, lectures, class discussions, and independent

reading. The students also modeled the process while constructing an “Art Cart” for the schools

homecoming celebration. The students had to develop a cart that reflected the WEGA program.

They had to work with the criteria and constraints given them (ex: $50 budget, space, materials).

This was a hands-on way to have them work through the process, while getting first semester

freshman involved in school activities.

       The Shape Memory Alloy portion of the lesson was presented to the students over a

three-day period of time that included a short lecture on the basics of SMA’s, participatory

examination of the springs, and small group research on SMA’s. On day three the students viewed

a video clip from Discovery Channel’s, Dirty Jobs

( on the day in the life of a
Cynthia Eppes                                                              E3 Final Report
Westside High School – Houston ISD                                      November 26, 2008
Roughneck. The video showed the students the working conditions on an oilrig platform. This

clip pointed out the excessive amount of drilling fluid (Mud) on the platform floor. This causes a

potentially unsafe working environment as well as potential for environmental contamination. The

students were given this scenario to design a valve application using SMA springs to solve the

issue of the excessive Mud on platform of the drilling rig. Over the next three weeks the students

worked in groups to come up with a design solution. The students were responsible for the

following items by the end of the third week: a prototype, oral presentation, detailed drawings, bill

of materials, proof of concept, environmental impact report and power point to highlight topics

during presentation.

        In the beginning the students were excited about being able to work with the SMA springs

and the power tools, but as the work progressed they found it difficult to work in groups and stay

focused. Many of the students were frustrated with working in teams and all the management that

goes into this process. The WEGA teaching team put interim deliverable due dates to help keep

the students on track. The students did not make the connection that the entire project was

developed to have them actually work through the design process they had just learned about.

Students are not in the habit of having to apply what they are learning, they are much more

comfortable learning the material to answer questions for a multiple-choice test vs. applying the

material they just learned.

        The students enjoyed working with the different materials and the freedom to come up with

their own solutions. They had difficulty staying with in the criteria (materials to be used) and

constraints (time) that were given to them. The students did not enjoy working in groups. They

found it difficult to manage the workload and individual work styles that come with working in a

Cynthia Eppes                                                               E3 Final Report
Westside High School – Houston ISD                                       November 26, 2008
       Project-based learning is exceptional for seeing the students apply what they have been

taught. This was very difficult first semester freshman. These students have not been exposed to

many opportunities to apply what they have learned past taking exams. They are much more

comfortable learning the material to take a multiple-choice exam, than making the connection

between something they have read or discussed and applying it towards a problem.

       Going forward this lesson will be the closing project for the spring semester. The WEGA

teaching team plans on working with the students on team building and time management prior to

having the students take on such a design project. This could not be completed in the timeframe

given to present the lesson. Originally we had the students come up with the materials that were

needed to construct the valve – example – size of PVC pipe, etc. They did not put in the effort to

come up with the materials and this delayed the gathering the material, which in turn delayed the

beginning of the construction. In the future the specifics of the material to be used to construct the

prototype will be established prior to presenting the students with the project.