The Roller-Float

It was 10:00 am on the passenger spaceship Vestigo, and River was closely studying a picture from the planet Pax. The image was of a rocky, reddish-brown riverbank. River was being trained, along with others kids her age, in the transportation division of the Vestigo. Training modules were prepared to cater to students’ aptitude and skills, centered on personalized learning. The spaceship was making the journey to Pax, a planet with conditions that could support life. Pax was covered in long intertwining rivers with rocky banks, which would make transportation difficult. The transportation division was tasked to design and engineer a device that could be relied on to transport people across the terrain of Pax. The division had challenged its students to create such a device in teams. The best-suited device would be selected for use on Pax.

River had brainstormed with her teammates and they had come up with two ideas: a multi-terrain vehicle with adjustable wheels and retractable floats or a specially designed boat. They had decided to use the wheeled vehicle because it could travel on water and land, so it would be better suited to Pax’s terrain.

Now it was time for River and her teammates, Lark, Deja, and Lake to complete the next step of the engineering design process: to create a plan and make a prototype of it. First, they decided how the vehicle would run. “One of our requirements is to make the device energy efficient,” said River. “Pax gets many hours of sunlight during the day. The vehicle could be solar-powered,” suggested Lake, and the team agreed.

Next, they chose the materials the device would be made of. For the vehicle’s body, River chose a composite material called BCM78, which was biodegradable to minimize environmental impact, and had high impact strength. For the wheels, a Materials engineer recommended BCM34, a composite material with a rubber-like component that would hold against sharp rocks, but act as a rubber tire on flat surfaces. The transparent cover would be made of impact-resistant glass, and the interior of the vehicle of plant-based polymer.

Then, they planned how the device would get across rivers. A sensor would be installed on the underside of the front of the vehicle, which would sense when it was at the edge of the river. Then the extendable front wheel frame would reach over the water in “Aquatic Mode”, with retractable floats coming out of the vehicle’s underside and landing on the water. The back-wheel frame, with its own floats, and the rest of the vehicle would then join the wheel frame, and a boat motor would propel it across the river. On land, the front wheel frame would resume its usual state and pull the rest of the device up.

For the prototyping phase, specialized robots were programmed to follow the protocols of assembling the vehicle. After inspection, the prototype, named “Roller-Float 1”, was ready to test.

The Roller-Float 1 would be tested in an artificial river environment onboard the ship in front of the Vestigo’s transportation division approval board, which would assess contestants’ devices and give them advice on iteration. The Roller-Float 1 sat ready on one side of the artificial river. River used a remote control to move it forward. As planned, the front-wheel frame switched to Aquatic Mode and the vehicle moved smoothly onto the water. On the way across the river, it shook slightly but remained on course. At the other side, the wheel frame retracted its floats and reached up to get on land. It began to pull the vehicle up, but suddenly stopped! The front-wheel frame wasn’t strong enough to pull the vehicle onto land. The Roller-Float 1 was tested many more times with the same result.

The board discussed the vehicle’s performance. “We have concluded our assessment and will now share the results with you,” announced a board member. “Your device transitions into the water smoothly, but it shook while traveling through the water and cannot transition out of the water.” “First, its shaking on the river’s surface may be caused by the small size of the retractable floats. And the Roller-Float’s inability to leave the water may be because of the lack of extendability of the back-wheel frame as well as the small front wheels.” River, Lark, Deja and Lake thanked the board and started iterating.

“The first problem, concerning the floats, can be fixed easily,” said Lark. “We need to increase the surface area of the floats to make them sturdier.” For the transition out of the river, River and her teammates decided to make the wheels bigger and add an automated extension to the back-wheel frame. Now they would modify their prototype and test it again.

On the day of the second test, the newly improved Roller-Float 2 was ready. This time, it moved across the water smoothly, and onto the bank easily. The board was satisfied with the performance. The next day, the Roller-Float 2 was announced as the winning vehicle. In the following months, River and her teammates continued to make upgrades to the Roller-Float models. Roller-Float 3 could operate much faster, and Roller-Float 4 was wheelchair accessible. Soon, the Vestigo began to teach classes to passengers on how to safely operate Roller-Floats and made policies about their use. River and her teammates had engineered the next vehicle to be used on Pax.

Annotated Bibliography

1. Resource: Engineer Girl-What Is Engineering Design?
Author: National Academy of Engineering
Date Retrieved: 1/15/2020
Description: This web page explains the steps of the engineering design process.

2. Resource: RSC.org-Composite Materials
Author: Royal Society of Chemistry
Date Retrieved: 1/20/2020
Description: This pdf explains what composite materials are and lists early and modern examples of
them.

3. Resource: EngineerGirl: Mechanical Engineer
Author: National Academy of Engineering
Date Retrieved: 1/25/2020
Description: This webpage lists the skills, education, and salary of a mechanical engineer.