The goal of R.A.B.E.K. Teaching Systems was to create a teaching device for disabled students. Marvin Picollo Elementary School teaches the most severely disable students in the Reno area. The age of the students ranges from 3 to 22 years old. The severity of each disability varies from student to student, making it hard to design a device applicable to a wide range of students. Therefore the team designed a simple user interface for the students to use. The Marvin Picollo Teaching Device helps students improve hand-eye coordination, cause and effect, and motor skills. A radio controlled car was redesigned along with a new controller design. The Marvin Picollo Teaching Device is easy to use and has visual aids to help the students interact with the device. The controller has multiple functions to challenge the students as they improve. The controller was designed to be placed on a table or wheelchair attachment. The Marvin Picollo Teaching Device helps students develop important skills while having fun using this device.
The controller will allow the students to control the RC car’s movement in the forward, reverse, left, and right directions. The RC car controller has an Arduino microcontroller that is programmed to receive user input in the form of pressing a button to control the RC car. Each button is a different color, can illuminate and is in the shape of an arrow to aid the students with understanding what each button does. The RC car contains four colored arrows that correspond to the same arrows on the controller. These arrows illuminate to help reinforce what is happening when a button is pressed. For example, when the green forward arrow is pressed, the green front arrow on the car will illuminate and move forward.
Proof of Concept
For the proof of concept, a simplified controller was constructed and was programmed to light up a LED light corresponding with each button that was pressed in order to test the user interface. The team then met with the students at Marvin Picollo Elementary School to observe their interaction with the controller. Key design observations included sensitivity, size of the controller, durability, button design, and graphics. These observations helped the team provide the students with the best product and learning experience.
The controller and RC car were designed with a set of specifications to ensure that they will meet the needs of Derek (the project sponsor from the school) and his students. The Engineering Specs and Implementation table shows what the specifications were for the controller and RC car. Most of these specifications are qualitative meaning they cannot be calculated, but there are a few specifications that are quantitative and were calculated. The quantitative specifications include the size of the controller (or weight) and the battery life. By including these specifications to the designs, the controller and RC car out-performed store bought RC cars.
Design for X
The team also needed to focus on various design factors. These factors can be seen in the Design for X table below. These Design for X (DFX) factors include cost, value, reliability, maintenance, and environment. The table explains how these factors were included into the design of both the controller and RC car so that the team could avoid having issues during production or after the product is fully developed.
The fabrication process started with the controller. The team decided on using an off the shelf hard case as the housing for the controller. First was to CNC cut the polycarbonate panels to fit the cover, arrows, and switches that complete the controller interface. The directional arrows were also CNC cut then drilled for each LED light to be inserted. Each arrow and the panels were then painted to increase aesthetics.Touch sensors and LEDs were attached to the buttons and soldered to the printed circuit board (PCB) and connected to the Arduino. The electronics inside the controller were fixed using Velcro and the button housing was then inserted into the pre-fabricated hard case.
RC Car Fabrication
Once the controller was completed, next was the RC car. The chassis and mecanum wheels were purchased to simplify the design. The wheels were then easily mounted onto the existing RC car axles.
To fabricate the body the team purchased a fiberglass repair kit and shaped a custom body mold from floral foam. The next step was to sand the mold down the correct size needed and desired shape. Then fiberglass and resin were applied over the foam mold. After 24-48 hours the fiberglass was cured. With the fiberglass fully hardened, body filler was then applied and sanded multiple times until a smooth surface was achieved. Holes where then cut in the body to fit the polycarbonate arrows with LEDs. Paint was then applied to the body and arrows. A piece of polycarbonate was cut to the size of the body where it attaches to the chassis. The LEDs were then soldered onto the PCB. Velcro was then used to hold down the Arduino, PCB, Xbee transceiver, and battery to the base of the RC car.
The final design was a huge success. The students at the school were very exciting when they were able to use the controller and watch the car move. The students started out with the challenge mode which resembles the game Simon Says. The controller randomly generates different arrows to be pressed. For example, the forward arrow lights up indicating that the button needs to be pressed. With the students successfully using this mode, the controller was switched to free mode which means the user can drive the RC car on their own terms. Again the students were able to hold down different buttons and drive the RC car where they wanted.
MEET THE TEAM
Alex Hartman was the team leader for R.A.B.E.K. Teaching Systems during the Fall semester of 2014. Alex has lived in Reno, Nevada his entire life and always planned to study engineering at the University of Nevada. In the fall semester of 2011, he began his career as an undergraduate studying Mechanical Engineering. Alex has since graduated with a B.S. in Mechanical Engineering and a Minor in Mathematics. Alex has become very proficient with SolidWorks and AutoCAD from his undergraduate research in the Composite and Intelligent Materials Lab and through an internship with ConAgra Foods. These skills will greatly benefit the team. In Alex’s free time, he enjoys camping, hiking, building vehicles and off road racing.
Rene Gonzalez got his degree in Mechanical Engineering at the University of Nevada, Reno in the Spring of 2015. Rene enjoys the outdoors and when not studying, he likes to spend his free time cycling.
Evan Fine graduated from the University of Nevada, Reno in May 2015 with a Bachelors of Science in Mechanical Engineering. Evan was born and raised in Reno, NV and graduated from McQueen high school. He is currently working as a drafter/designer at MMI Engineering specializing in HVAC and plumbing systems. During his free time, Evan enjoys spending time in the outdoors camping, hiking, and off-road racing.
Brandon Tollefson was the leader for the Spring semester during this project. Brandon obtained a bachelor’s degree in mechanical engineering at the University of Nevada, Reno in the Spring of 2015. During the summer of 2014 he was a manufacturing engineer intern at Aerojet Rocketdyne. He was part of the lean manufacturing team, working to reduce the manufacturing cost and increase efficiency of the manufacturing cell. He has experience in SolidWorks, MATLAB, and project management. Brandon enjoys camping, dirt biking, scuba diving, fishing, and wakeboarding during his free time.
Kanin Prucksakorn attended the University of Nevada, Reno and obtained a bachelor degree in Mechanical Engineering and a minor in Mathematics. He has worked as an IT and a Data Analyst before going back to school full time to pursue an engineering degree. He has received his Associates of science with engineering emphasis at Truckee Meadows Community College before transferring to University Of Nevada, Reno. He has experience in Solidworks, Autocad, welding ,fabricating and working on vehicles. His hobbies include Rock Crawling , building vehicles, and any outdoor activities.
The team would like to thank Joao Braz and Brian Nicols for assisting with the microcontroller programming as well as Dr. Aureli and Dr. Geiger for their guidance. The team would also like to thank Derek Cromer and the rest of the staff and students at Marvin Picollo Elementary School.