Our Final Product

Testing Procedures

Once the hovercraft neared completion, Tony and I began testing the electrical units. As long as my hull did not break, my testing was successful. Below you can see Tony and myself checking the lift and propulsion systems and how the hull held up under pressure. Testing commenced midway through construction when we were able to easily access the inside of the hull.

Final Log

Contacted mentor. The fine balmy night was last Thursday, it was a complete success.

Week 36 Log B

TONIGHT IS THE FINE BALMY NIGHT!

Week 36 Log A

We're done! Now we just have to paint our proejct and we're set for the fine balmy night

Week 35 Log B

We've tried a few different skirt ideas to see if it affected our project. WE're going to go with the original design.

Week 35 Log A

It kind of works!! There's less friction but its not totally friction-less. We're going to try to make it more efficient.

Week 34 Log B

We have leaf blower mounted and just hve to finish attaching the skirt. Tuesday is D-Day

Week 34 Log A

I was taking the AP Stats Test

Week 33 Log B

TC and I are going to a different hobby shop today to see if we can get any more parts. Stay tuned...

Week 33 Log A

Plans For The Week

• Finish attaching leaf blower
• Start attaching skirt and/or propulsion system

Week 32 Log B

TC and I started cutting the lift system into a size more suitable for mounting. DA is ordering more things for us to use. We're going to be very curnched for time

Week 32 Log A

Plan for the Week

• Building

Week 31 Log B

TC and I finally have SOME parts so we're starting working on the electrical parts. We have the leaf blower for lift so we're going to be working with that today and next week mostly.

Week 31 Log A

AC and I went to Home Depot, Lowe's and Radioshack this weekend. We got some parts for ourselves so that we can actually start making progress

Week 30 Log B

Tony and I are getting crunched for time so we're bypassing the Board of Ed and just buying our own parts from Ebay. It's getting too ridiculous waiting.

Week 30 Log A

Plan For The Week

• Get materials ordered

Week 29 Log B

Traveling to England today!!!

Week 28 Log B

Things Accomplished

• Presentations Completed
• Sanding Pieces Completed

Construction

Introduction

Miniature Hovercraft Project

Victoria Rotberg

Marine Academy of Science and Technology

Systems Engineering II

Photo from:  http://anggun3.files.wordpress.com/2008/05/hovercraft.jpg

Week 27 Log B

Things accomplished

• Pieces cut to size
• Commencing sanding

Press Release

 

Press Release: Miniature Hovercraft

Figure 1: Example of a Mini-Hovercraft

Taken from: http://www.hov-pod.co.uk/photo/showroomhovpod.jpg

By: Victoria Rotberg

March 12, 2010

Introduction

            The 21^st Century is all about modernization and innovation. The number of technological advancements in our generation is at an all time high. Many of these advancements are intended to simplify many tasks in our daily lives, whether they are general or specific to certain tasks and jobs. The National Oceanic and Atmospheric Administration lab stationed on Sandy Hook, New Jersey takes regular water samples of the surrounding water. One of these tests includes gathering samples of water to see the amount of plankton in the water. The organization has requested the students of the Marine Academy’s Systems Engineering II class to build a miniature hovercraft that can deploy a plankton net. An example of which can be seen above in Figure 1.

Project Description

            The main purpose for the miniature hovercraft is to leave the ecosystem unharmed and undisturbed. Because it will hover above water, it will not disrupt the animals or debris on the bottom. It will also be remote controlled so that it can be used from a safe distance. This will reduce human presence in the marsh. VR is the structural/civil engineer for the hovercraft project and her job is to design and construct a sturdy structure of the hovercraft that will house the necessary equipment that will make the hovercraft systems work. A plankton net will be positioned inside the back of the hovercraft in front of a hole that will allow it to be deployed and retracted. A cavity inside the hovercraft will house the plankton net so as to not get the electrical necessities wet.

Mentor Involvement

Each student has a mentor for his or her project. The mentorship program is designed to aid students in their specific field of study or research. So far her mentor has been guiding her and giving her advice on which materials to use and the quantity of each. Also, her mentor has been giving her advice and on how to put together a certain part of the hovercraft or correct her on points that he does not think will be feasible.

STEMM

So far the major concern has been weight. The hovercraft will not hover if it does not have sufficient power to lift it. The power is not VR’s concern but she has been working to decrease the weight so that her partner, TC, has an easier time of things. She has picked 3-layer plywood instead of 5-layer. This will lower rigidity but it will weigh significantly less so the benefits out weigh the losses. Another big factor that ties in with the hovercraft’s weight is stability. If the hovercraft is not perfectly symmetrical or is not built properly, it has the possibility to capsize.

Presentations and Expectations

The upcoming formal report of progress presentations will highlight the extent of VR and her partner, TC, construction thus far. The presentations are scheduled to occur on the 11th, 12th and 15^th of March. They will discuss what other steps they will need to take to complete their construction and get their project up and running and ready for testing. After presentations are concluded TC and VR will continue working until their project can hover and deploy and retrieve a plankton net as stated in their design brief.

Summary

            In closing, VR and her partner have begun their construction on their senior project in their System Engineering II class. They are building a Mini-Hovercraft that will be able to take plankton samples using a plankton net. Their Formal Report of Progress presentations will commence on the 11^th, 12^th and 15^th of March in the Marine Academy’s Media Center. Soon they will have their project completed and ready for display on that fine, balmy night in May.

Week 27 Log A

Plan of the Week

• Continue construction

Week 26 Log A

Plan of the Week

• Construction
• Press Release

Week 25 Log A

Plans For The Week

• Materials needed changed: plywood and possibly fiberglassing materials are available at school so  all I need is my skirt material and vinyl cement which I'm waiting for a final bid to complete the 3
• I can begin construction but I must wait on my partner to decide on a motor that is acceptable because it could change my dimensions

Week 24 Log B

• Two bids pending: followed up on them today and I had to re-fax them. Should hear back from them by monday.
• Started Press Release Paper

Week 24 Bid Process Log

I have four bids pending that will give me a complete set of three bids per item that I need.

Week 24 Log A

Plans for the Week

• Order building materials

Week 23 Log B

We've had off for the past two days due to inclement weather. So I have done nothing.

Week 23 Log A

Plan of the Week

• Fill and remaining bids

Week 22 Log B

Things Accomplished

• Companies found, bids need to be written for each

Week 22 Log A

Plans for the Week

• Complete remaining bids for orders

Week 21 Log B

Things Accomplished

• Worked on Calendar
• R&R after midterms

Week 21 Log A

Midterms Week

Week 20 Log A

Plan of the Week

• Do Presentation Outline
• Prepare for Presentations

Week 19 Log B

Things Accomplished:

• Posted Developmental Work
• Posted STEMM Report

STEMM Analysis

The NOAA lab needs to catch plankton in the inaccessible parts of Sandy Hook; however they do not want to disturb the ecosystem. In order to overcome this problem the NOAA lab has requested that the students of the Systems Engineering II class to design and construct a miniature hovercraft. The hovercraft will be suspended above water level by air propulsion so as to not disturb the environment. My portion of the project is to design and construct a sturdy structure for the hovercraft which will house the necessary equipment required for the hovercraft to function. The solution that AC and I have developed is shown in Figure 1a (below). There are two components to my design: the hull and the skirt. The hull has a basic horizontal, trapezoidal shape and will be constructed out of marine plywood. The skirt does not have a set structure because it is used as an inflatable material but it will be fastened to the bottom of the hull. In Figure 1b (below) the basic side of the hovercraft can be seen. The small, open cavity will allow for the plankton net deployment system to be attached and function.

Figure 1b (left): Back view of hull and skirt combination. Cavity can be seen here.

Figure 1a (above): Front view of
hull and skirt combination.

The majority of hovercrafts are used for the transportation of people over short distances. The hovercraft that AC and I have designed is an innovation of this traditional hovercraft in two ways. The first way is that our hovercraft is miniature in size, and the second way is that the hovercraft will be used for taking plankton samples instead of public transportation. Figure 1a and Figure 1b (above) show only my component of the project. My structural design will be combined with the electrical component which is being designed by my partner AC. My particular component combines different types of engineering; the construction of the hull combines the types of engineering such as architectural, civil, construction and structural. To build the hull and skirt I needed to research different types of materials, wood for the hull, and textiles, fabric for the skirt, as well. These materials and textiles will be used in a delicate ecosystem so I had to keep environmental engineering foremost in my mind. And now, having researched all the listed types of manufacturing that were on the rubric for class I think none of the types apply to my project. The closest type would be mass customization. My project does not need to be mass produced and only two pieces out of the nine are identical. The types of manufacturing categories are very similar to the types of engineering listed previously; the main categories would be construction and textile manufacturing.

The main physics concept for the hovercraft project as a whole is based upon air pressure. Air escapes from the bottom of the skirt and tries to reach equilibrium with the surrounding atmosphere; to do so the air must travel between the skirt and ground. While it does this the air reduces friction between the ground and the skirt, allowing the craft to glide with little drag. This process can be seen in figure 2 and is closely related to Bernoulli’s Principle and how planes fly.

Figure 2: How to Create Lift
Taken from: http://filebox.vt.edu/users/sfagg/teched/html/activities_hovercrafts.htm

Fun Fact: Hovercrafts are not street legal.



One of the main materials I am constructing the hovercraft with is marine plywood. Marine plywood differs from normal plywood in that a phenol-formaldehyde resin is applied to make the pores of the wood smaller so that destructive moisture does not get in. The chemical composition for phenol-formaldehyde resin can be seen in Figure 3.

Figure 3: Chemical composition of phenol-formaldehyde
Taken from: http://www.lookchem.com/keyimages//2009-9/4290cd1d-c4c6-4ee4-b047-d9f2e60e8f7a.jpg

In addition to the marine plywood, an epoxy resin will be applied to the plywood to fiberglass it and make it even more waterproof. The chemical composition of epoxy resin can be seen in Figure 4.

Figure 4: Chemical composition of epoxy resin

Taken from: http://www.baggressive.com/ld/content/ep.gif

The hovercraft project doesn’t just contain physics and chemistry; there is also a biology aspect: the plankton. Plankton is defined as “the passively floating or weakly swimming usually minute animal and plant life of a body of water” by Merriam-Webster Online Dictionary. In figure 5 below, you can see the distribution of plankton in all the oceans. As seen below, the coast of New Jersey has a high abundance of plankton. Plankton can range in size of a few centimeters to micrometers. A range of plankton can be seen in figure 6 below.

Figure 5: World map showing the abundance of plankton in the ocean. (Green = high abundance. Light green = medium abundance. Blue = low abundance.

Taken from: http://en.wikipedia.org/wiki/File:World_plankton_prevailence.PNG

Figure 6: Series of phytoplankton
Taken from: http://drake.marin.k12.ca.us/stuwork/ROCKwater/PLANKTON/phytodrawings.gif

Much to my surprise there is a long and precise process to make marine plywood. Normal plywood is made by gluing at least three thin layers of wood as can be seen in Figure 7. Many different kinds of wood can be used to make plywood. “At the plywood mill, cut logs are brought by chain conveyor to a debarking machine that uses grinding wheels and water jets to smooth the surface. Another conveyor transports the logs to a circular saw that shaves them into chunks, called "peeler blocks," that are just over 8 feet long. The peeler blocks next undergo a softening process to make them easier to slice into the thin veneers that make up the wood layers. The softening process, which can last from half a day to two full days, is done with either the application of steam heat or total immersion in water. Once heated, the peeler blocks are sent through a precision lathe with a cutting blade, which shaves a succession of veneers from the block until very little is left. Defective pieces are discarded at this point. The veneers, still a bit over 8 feet long, are next cut into widths of just over 4 feet so they can later be trimmed to standard 4x8-foot sheets. The veneer pieces are put through a heated dryer, after which they are stacked for later use.” (Information from http://www.ehow.com/how-does_5001884_how-marine-plywood-made.html). Once the layers of wood are glued together and dry phenol-formaldehyde resin is applied to the plywood to make it more water-resistant.

Figure 7: Cross section of a 5-layer piece of plywood.
Taken from: http://www.buy-plywood.online-timber-sales.co.uk/images/PlywoodExpandedView.jpg


Polyester fabric is a versatile and important man-made fabric. It has an outstanding characteristic of resisting wrinkle and springing back into its crisp smooth shape. It is strong, and soft hand. The fabric is resistant to stretching and shrinkage. These are quick to dry and are resilient. It has an excellent pleat retention property. It requires minimum care and is easily washable. Polyester is a polymer, which is produced from the coal, air, water, and petroleum products. It was first commercially produced in 1953 by E. I. Du Pont de Nemours & Company, Inc. in the United States. It is next to cotton in worldwide use. Polyester fabric blends well with fabrics. It blends with wool, acetate, or rayon to improve the durability of the fabric and even to make it easy washable, if the percentage of polyester is high. It adds the quality of wrinkle resistance to the fabric and eliminates crushing of napped fabrics, and reduces fading. The fabric aggravates pilling problems after being blended with wool. Much of the fabric is threaded using microfibers as shown in Figure 8.

Characteristics of Polyester Fabric


• It is strong, stretchable, and durable.

• It does not wrinkle.

• It does not shrink.

• It is resistant to crease.

• It is resistant to mildew.

• It is abrasion resistant.


• It is resistant to most chemicals.

• It is not damaged by sunlight or weather.

• It dries quickly. It is crisp and resilient when wet or dry.

• It is easily washed.

• It does not absorb moisture making it hot and clammy when worn in hot temperatures.

Uses of Polyester Fabric

• Polyester clothing has a good stability and strength and is resistant to stretching and shrinkage. It is not damaged by sunlight or weather. It is widely used as dresses, blouses, jackets, separates, sportswear, suits, shirts, pants, rainwear, and children-wear.

• Polyester fabric is manufactured in many weights and it is used as fiberfill in pillows and upholstery. In upholstery, polyester is generally blended with wool to eliminate crushing and reduce fading.

• Polyester is also used in casement curtains, draperies, floor coverings, throw rugs, bedding, and as a cushioning or insulating material.

Information on Polyester is taken directly from http://www.fabrics-manufacturers.com/polyester-fabric.html
 

Figure 8: Cross section of a microfiber thread that is often used to make fabric.
 
Taken from: http://www.maintenancesuppliesmag.com/images/article/1242762999558_Microfiber_Cross-Section.jpg
 




The hovercraft project is an innovative idea requested by the NOAA lab workers. It deals with construction, textiles, structural design, and many other types of engineering. The final product of the hovercraft will have a trapezoidal hull made of marine plywood and a skirt made of PVC coated polyester. The construction of this part includes the physics concept credited to the physicist, Bernoulli. It also deals greatly with surface area and dimension ratios. Soon we will begin construction and the structural and electrical parts of the hovercraft will be combined to create the finished product.

Plan of Procedures: Attach Skirt to Hull

Week 19 Log A

Plan of the Week

• Handed in completed Developmental Work and Math/Science Analysis
• Need to post work on blog

Week 18 Log B

Things Accomplished

• Half of Math/Science Completed
• Developmental Work Needs Adjustment

Isometric View: Skirt

• Skirt will be made out of a PVC coated polyester fabric

Week 18 Log A

Plan for the Week:

• Complete Developmental Work
• Complete Math and Science Analysis

Orthographic Views of Hovercraft (With Labels)

Exploded View of Hovercraft (Parts Labeled)

Rendered Isometric View of Hovercraft

Plan of Procedures: Assembling Hull and Cavity Together

Plan of Procedures: Hull Assembly Steps

Plan of Procedures: Cavity Assembly Steps

Plan of Procedures: Materials Processing for Hull

Plan of Procedures: Lists