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Monthly Archives: February 2013

Automated Heliostat Cleaning

In this series of interviews with the ENGS 90 groups this week we spoke to members of group 2 working on developing an innovative solution for cleaning of heliostats.

Heliostats- the shiny reflective surfaces which concentrate the sun’s power and use this to generate power, so what keeps them shiny? As of now its masses of trucks moving around washing and cleaning these surfaces, but what if it could all be automated? That’s precisely what group 2 of ENGS 90 is striving to achieve in their project.

To explain in more detail, heliostats are the devices which collect and focus the sun’s rays on to a heat exchanging liquid which is contained either in a tube structure along the length of the heliostats or in a central tower. This arrangement forms the core of the concentrated solar power technology- which is the most promising in terms of energy yield.

Group 2’s innovative solution for cleaning heliostats consists of an autonomous, highly specialized robot which is capable of mounting the heliostats and cleaning them. This project, like all others at Thayer, is a highly interdisciplinary project with the team comprised of members having backgrounds in different branches of engineering carrying out a wide variety of tasks.

The team’s tasks encompassed the whole gamut of engineering right from machining the metal parts, printing or fabricating the plastic components to programming and putting together the electronic control circuitry. All these activities were carried out from scratch in the machine shop, the large frame projects lab and other allied labs at Thayer.

Thomas described the major challenge the team faced as “designing the robot in such a way that it can successfully navigate all the obstacles which it will face on the field.” Further Benjamin described the process of writing reliable code for the robot as an additional challenge. Finally Callen and Alyson mentioned figuring out how the cleaning instruments should be optimally placed on the robot as a problem of concern on which they worked.

The team consists of Thomas Balch BE, Benjamin Blier ’13, Callen Votzke ’13, Anne Lape ’13 and Alyson Pickett BE.

Shown below are some pictures of the project team and their work.

 

 

Thanks for reading. Hope you’ve enjoyed it!

-Pavan R. Yerram

 

Innovative Medical Pill Vial

This week’s project involves an innovative take on the mundane pill bottle cap. So how many times have you forgotten taking a prescribed pill or maybe taken it twice just to be safe? It happens to everyone, even the ones with the best of memories, once in a while. So since no one has come up with a solution to this, this is precisely what group 14 of ENGS 90 is working on.

Eric described their team’s project as a “better designed pill vial that mechanically indicates the next time a patient should take their pill.”

So how did they go about reinventing a better version of something daily? Eric explained further “we utilized SolidWorks as well as 3-D printing capabilities at Thayer. The resources provided by the machine shop were critical for the success of the project, and allowed the team to deliver good designs and prototypes to the project sponsors.”

Well that’s all I’m allowed to say about this project. Eric was kind enough to explain the project in further detail and it truly is innovative. I won’t be surprised if the product does become the reigning type of pill vial in the market.

Here are a few pictures associated with the project:

 

 

We hope you’ve enjoyed it.

 

-Pavan R. Yerram

Kristian’s research

In this blog we learn about a researcher’s work in the machine shop. The researcher in question is Kristian who‘s a fourth year PhD student in Prof. Brian Pogue’s lab. Prof. Brian Pogue’s a leading biomedical teacher and researcher and you can learn more about his work through the following links:

http://engineering.dartmouth.edu/people/faculty/brian-pogue/

http://graduate.dartmouth.edu/about/newdean.html

It was while I was on a leisurely jaunt through the machine shop looking at the work students were doing that I came across Kristian who was busy machining his device and racing against time to get it done before the shop closed. Well, research at Thayer not only involves routine lab work but also the occasional trips to the machine shop to build your own machines. But how do novice machinists start building so quickly? It is due to the hands on guidance from the instructors, the TAs and the design fellow.

Since what Kristian is doing is very novel and hasn’t been published yet I won’t be going into the technical details much, but suffice to say it is pretty interesting.

Kristian’s projects are in the field of biomedical technologies and the project he is working on falls under a larger project titled “Fluorescence guided neurosurgery”, a project in which he explores the use of fluorescence to help surgeons and medical practitioners differentiate between diseased tissues and healthy ones. For example tell apart cancerous tissues from the healthy ones during surgeries.

The photos below show the device which Kristian machined in the machine shop, he then anodized it to give it a better finish since it’s going to be used not only in the lab but in medical hospitals as well. The device consists of place holders for LED lights which are arranged in a circle and in the center is placed a camera which captures images extremely fast. This allows the researcher to have his/her sample inspected through fluorescence which is excited in the samples by the LED lights. What’s interesting about the LED place holders is that they have been machined to be adjustable, thus making the device extremely flexible- a proof of machining sophistication.

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Well that was about Kristian’s work, yes it’s a little short on the details of what Kristian’s doing, but we sure will get you more on this once the work is published in one of the journals. Meanwhile feel free to go through the links given for Prof. Brian Pogue’s lab and his ongoing projects. Further do visit our Facebook page for more photos on this project and other interesting stuff going on at the machine shop.

-Pavan R. Yerram

ENGS 90-Design/Build 10HP Walvisstaart Propulsion system

In keeping up the interesting conversations with engineering students carrying out their capstone projects, this week we spoke to Ethan Dreissigacker whose team, as the title points, is tasked with the design and development of a 10 horsepower propulsion system for use in boats. “Walvisstaart” in Dutch means a whale’s tail. The system’s named so because it tries to mimic the movement of a fish’s tail. Since the Netherlands based sponsor Walvisstaart systems wants to make such propulsion systems for large boats plying the water ways of Netherlands they chose the whale’s tail as their name.

So what is Ethan’s team doing?

Ethan’s team is building a fully functioning prototype of the propulsion system albeit on a small scale. The design is inspired by the movement of a fish’s tail, hence the novelty of the undertaking. Not only is the model fully functioning, it is also scalable thus increasing the complexity of the project.

And how did they go about their project?

It’s a little difficult to convey details of this project in only words, for which reason I’ve included here a few pictures which you can follow along to get a better view of what these guys have done.

In the picture below Ethan shows us a model of the fin which they made by rapid prototyping using the 3D printing machine in the machine shop. They first developed a blue print of the fins using a 3D CAD (Computer aided design) software called SolidWorks. SolidWorks provides a file which is then input to one of the 3D printing machines which then builds the rapid prototype model of the design.

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Once the rapid prototype is built it is then used for building a silicone mold using which the final components are fashioned, in this case the final fins built of resin and fiberglass are fashioned out of the silicone mold. In the picture below we see the final fins painted bright.

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In the following pictures we see the other components of the system, the rotor, the gears and the metal housing frame all of which had been machined in the machine shop from scratch.

 

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So finally since they have successfully built the model what else are they looking for?

Ethan described their aim is “to test as many iterations of the system as possible so that they could look for all the things that could break and fix them.” Given that the machine shop and its instructors are just across the hall, breaking things and fixing them is not a problem hence the freedom to make the system as resilient as possible by stretching it to its limits.

Ethan further describes their goal is “to bring the real system as close as possible to the ideal system designed and modeled on a computer,” the computer model doesn’t account for real world problems in machining hence achieving this is quite an objective.

Well that’s about the whale’s tail. We hope you have enjoyed it and we’ve got a few more related pictures and videos on Facebook, they are even better and we’re sure you’ll enjoy them. Below is the link or visit our Facebook page at Thayer School Machine Shop.

https://www.facebook.com/media/set/?set=a.535794536454162.122831.221877084512577&type=3

 

-Pavan R. Yerram

ENGS 171-Vacuum Cleaner project

Six teams are doing eco-design projects for ENGS 171 (Industrial Ecology). The main idea behind the project is to analyze the different phases of product life-cycle and redesign the product such that it becomes more environmentally friendly. The main tool that the teams use is the CES Edupack 2012.

The team of MEM students Amogh Poudyal, Aaryaa Uprety and Shi Xu are working on redesigning the vacuum cleaner. The team had mid-term presentation last week where they disassembled vacuum cleaner and performed eco-audit in terms of materials, manufacturing, transportation, usage and disposal. For disassembling the vacuum cleaner, they used tools from couch lab such as Screwdrivers: Philips and Flathead, Hand saw, Hammer, Pliers, Wire strippers, Wire cutters, Paper blade and Scissors. According to the team, disassembling outer components of the vacuum cleaner was fairly easy as they were big parts and mostly polymers. They mostly used screwdrivers to take out the outer components. However, they had a tough time disassembling motor parts. Amogh mentioned it was especially hard for them to take copper wires out of the motor core and the cables. So, the team took help from colleagues from the instrument shop.

 

 

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-Aarya Uprety