Cal Poly Invention Helps Disabled Student Participate In Triathlon

Cal Poly students have invented a device that allows disabled 20-year old college student Joseph Cornelius to glide along the water, providing the sensation of swimming.

With no muscle control over his limbs due to cerebral palsy, Joseph still loves to exercise and has competed in 100 foot races with the help of his father, John Cornelius, under the team name “Team Joseph.”

Until now, he has been unable to swim because of the danger of water getting into his lungs. “Aquabullet,” the Cal Poly invention, is a hydrodynamic watercraft created by Cal Poly students Paul Sands, Lilly Hoff and Andrea Voigt for their senior project, and has been designed to reduce the risk of water entering Joseph’s lungs through use of a clear plastic splashguard.

Aside from the splashguard, Aquabullet is made up of a support system consisting of floats and mesh. The bow and headrest are both made out of Precision Board Plus donated by Coastal Enterprises.

The students designed and built Aquabullet after extensive research and testing in collaboration with Joseph and his father. Funding was provided by a National Science Foundation grant to Cal Poly, along with the support of donated materials from several vendors.

Aquabullet design mock-up:

According to Cal Poly student Paul Sands, “Michael Lara, Manager at the Special Olympics of Southern California, pitched the idea [for a senior project] to the entire class of Mechanical Engineering seniors at Cal Poly, and both Lilly [Hoff] and myself picked it as our number one choice. For years, the Mechanical Engineering and Kinesiology departments have collaborated on different projects. For this reason, Andrea Voigt, a Kinesiology major, was brought onboard with her considerable experience in swimming and working with people with disabilities.”

Finding the most ergonomically-comfortable device was challenging. “After testing 6 or 7 different crude mockups, searching for a design with the most comfortable position for Joseph, we decided on one that would allow him to lay on his stomach,” says Sands.

“Construction of Aquabullet was started by sanding and shaping a piece of 6 lb. Precision Board we cut from a larger block, followed by painting it with red acrylic paint and applying fiberglass,” recalls Sands.

After the fiberglass was cured and the rough edges filed down, a hard coat was painted over it consisting of a mixture of surfacing agent and laminating resin. Extensive sanding, followed by a 3-stage polishing process ensured that the headrest would be comfortable for Joseph to rest on.

The bow was made out of 8 lb Precision Board in the same process as the headrest, painting it with red acrylic paint prior to fiberglassing and sealing it.

After both pieces were finished, students fabricated the splashguard with the assistance of local motorcycle windshield manufacturer Rifle through an extrusion blow molding process.

Each piece was assembled together, completing the Aquabullet:

Aquabullets successful completion allowed Joseph Cornelius to successfully swim in the San Luis Obispo Triathlon, of which additional information can be seen at: Pictures of the event and additional information here.

At the completion of Aquabullet, the students had noted several proposed production and vehicle changes for the future, and Paul Sands plans to make improvements to Aquabullet, and also design another vehicle before he graduates this December. Long term goals include patenting the design and potentially producing it, as this form of an “Adaptive Sport Vehicle” has the potential to provide a therapeutic activity to many people with disabilities.

Paul can be reached at: psands22@gmail.com or (909) 583-5643.

Parties interested in additional information about Team Joseph can contact John Cornelius at: jcorn224@yahoo.com.

UCSD Human Powered Submarine Takes The Plunge

UCSD ASME students took the plunge with their Human Powered Submarine, “Legasea”, at the 12th International Submarine Races in Bethesda, MD, this past June.

The event was held at the Carderock Division of the Naval Surface Warfare Center in the David Taylor Model Basin, one of the largest ship model basins in the world. The competition consisted of 19 teams competing in a 100 meter race. Each team was required to design and build a one or two-person “Wet” submarine, which has a completely flooded hull and requires the crew members to breath SCUBA from an onboard air supply.

UCSD students designed and created “Legasea”, a 2-man, propellor-driven, Human Powered Submarine that was designed with SolidWorks and built from scratch by UCSD students. Students relied almost entirely on donations, both material and financial, to bring Legasea to life.

Coastal Enterprises was proud to donate Precision Board to the UCSD Human Powered Submarine team to use for their mold-making process for the submarine’s body.

According to Elliot LaBarge, team leader, “We planned to use the 10lb and 15lb. Precision Board we had to make molds we could pull the fiberglass body components of the submarine from. Since the submarine is 21′ long, we decided to make three separate molds and join them together – a task we learned was much easier said than done, due to the large size of the molds.”

Diversified Manufacturing of California was kind enough to lend their CNC capabilities and expertise to the students, producing three perfect molds from Precision Board PBLT-10 and PBLT-15 and spraying them with PLC Polyprimer 903 Black. Once the molds were back in the students hands, they coated them with a Honey Wax mold release compound and PVA (polyvinyl alcohol), and were able to successfully pull three separate body components – a fiberglass nose, center and tail.

Once the body components were ready, the battle wasn’t over yet. An extensive assembly process began followed by as much testing as possible before the race.

“Precision Board worked great because not only is it durable and able to withstand several pulls, but it also has excellent machinability, which really helped us bring the submarine we designed to life”, says Elliott.

When it came time to race in June earlier this year, Legasea placed 3rd in the two-person, propellor-driven category. Sub speed was measured by two timing gates halfway through the course, which recorded Legasea’s top speed at 3.42 knots. Unfortunately, a critical failure of the steering control rods rendered them inoperable, resulting in Legasea being unable to complete the final race.

The next International Submarine Races will be held in June of 2015, and Coastal Enterprises will be working closely with the new team leader, Mr. Alistair Twombly, as they redesign Legasea for the next competition.

Check out more info about this project on the official UCSD Human Powered Submarine website: http://asme.ucsd.edu.

Video of the final “pool test” prior to the race:

How Fast Can A Human Powered Vehicle Go?

How do you design a champion Human Powered Vehicle? Jonathan Sanders, Fairing Engineer of the University of Missouri Human Powered Vehicle Team gave me the details of this years competition winning build.

Background of the HPVC challenge:

Designed to provide an opportunity for students to gain valuable design team experience, the Human Powered Vehicle Challenge (HPVC) is a yearly competition put on by the ASME, or American Society of Mechanical Engineers. The HPVC sets the stage for students to demonstrate engineering design skills in the development of sustainable and practical transportation alternatives. As an all volunteer project with no school credits that will be awarded, members of these HPVC teams are all extremely dedicated and knowledge-thirsty students.

Design/Build:

Since the car will be powered entirely by the human driver, the Human Powered Vehicle is going to need to be quite aerodynamic – especially if it is going to be entered into competition drag races against over 30 different college teams. A key part of the design process is constructing the fairings, of which the master molds were made out of donated Precision Board Plus PBLT-10.

This was the first time University of Missouri students had used Precision Board Plus to construct the fairing molds. Last year they used insulation foam, fiberglass, and bondo, which has a high room for error, especially for newer students. According to Jonathan: “the high level of accuracy and time saved by using Precision Board Plus was a huge improvement over previous techniques, and the team cannot wait to use it again next year.” Jonathan was even kind enough to detail this years mold making process for constructing the fairings for us:

1. Acquire the basic criteria for the vehicle based on the released rules

2. Design and test a prototype frame and make necessary changes

3. Fabricate the prototype frame

4. Acquire rider data by taking rider body part measurements and determining range of motions of each rider by taking motion capture photos of each rider on the bike with high interest points marked by high output LED’s.

5. Construct a computer rider model using the rider data.

6. Using the model, construct a basic vehicle fairing (take into account thickness, mounts, clearances, etc.)

7. Run iterations of CFD by changing certain aspects of the fairing until the final fairingis completed.

8. Using the final model of the fairing, design models of the molds and create blocks of Precision Board Plus that correspond to the computer models.

9. Using the computer files, 5 axis CNC the molds

10. Remove any remaining machining marks in the foam, apply a surface hardener to the molds, and then finish the surface of the molds.

11. Lay-up the fairing in the molds using a wet layup and vacuum bag method and seam the fairing together accordingly once the parts have fully cured.

12. Mount the fairing to the frame and check clearances.

13. Remove the fairing, make paint preparations as necessary, and then paint.

14. Re-mount the fairing.

One of the key lessons Jonathan learned from his involvement with the Human Powered Vehicle Team is that many ideas are limited only by manufacturing capability. For example, last year students had a great idea of building a hollow crank to save on overall weight. However, a veteran team member pointed out that they were using 7075 T6 Aluminum, which is a non-weldable metal. Not wanting to give up, they began researching possible methods to remedy this.

What they found was a form of welding known as Friction Stir Welding, which uses lots of heat and friction to join metal without actually melting it or changing the properties, and is also the highest-strength welding technique available. As luck would have it, a different department at the University was doing work using Friction Stir Welding, and had the equipment needed. Unfortunately, after the initial crank was built, it was discovered during testing that it was slightly deformed beneath the weld, rendering it unusable. However, they were able to carry the experience gained over to this years build, where they successfully used a hollow crank made from Titanium and stir-welded.

In the car experience:

When asked about his experience as one of the drivers, Jon mentioned that “inside the car it is a very tight fit, but it is quite enjoyable to drive.” Top speed on a sprint run is about 45 MPH, and with a skilled driver and long straightaway, these vehicles could go as fast as 60MPH! All of the drivers are secured with a 4-point racing seatbelt, and each car is designed to withstand hundreds of lbs. of concussion force in the event of a crash.

Competitions:

Each year the HPVC has 2 different events: East and West competitions, which consist of several races at each event. The races are determine by finishing position, and the overall award is determined by total points from all of the races and the design competition. There are several different scoring events:

1. Design – 40% of total score. They placed 4th in the East Coast competition and 5th in the West Coast competition.

2. Female Drag Races – 15% of total score. Suffered a mechanical failure at the East Coast competition and still finished 2nd place. Took 1st place at the West Coast competition.

3. Male Drag Races – 15% of total score. Placed 1st at both the East and West Competitions.

4. Endurance Race – 30% of total score. 2.5 hour endurance race with 4 drivers for each vehicle. Finished 1st at to both East and West competitions.

Won the overall award for the West Coast competition and took second place to Rose-Hulman Institute of Technology by a single point.

In an interesting and rare turn of events, the University of Missouri and Cal Poly actually ended up tying in points at the West Coast Competition for the overall award. The University of Missouri ended up breaking the tie by winning all of the races. Congratulations to the University of Missouri for a job well done!

An excellent video of the HPV can be seen at: http://vimeo.com/41952419