Hunter Yeider, a young man with CDG, was the inspiration behind the creation of a customized off-road go-kart. Congenital Disorder of Glycosylation (CDG) is a rare syndrome that results in mental and physical disability by hindering the Glycosylation of proteins and lipids in an individual. Trail Runner’s go-kart was designed to give Hunter mobility and a sense of freedom while giving Faith, Hunter’s mother, peace of mind.
For more information on Congenital Disorder of Glycolysation please visit:
Trail Runner developed a prototype chassis that served as the foundation for the go-kart as most of the components of the go-kart are related to the chassis. The prototype was designed specifically for Hunter, and it was able to be quickly adjusted to fit him. This allowed Trail Runner to make modifications before the final chassis was fabricated. The prototype was constructed with slightly larger physical dimensions to accommodate unforeseen interferences.
The final design, as seen in the Solidworks 3D rendering above, that Trail Runner decided to pursue consists of several intricate components. The function of the go-kart can be described by focusing on the steering, power transmission, power control system, and brake system.
The steering is controlled through a standard steering wheel. The steering wheel is bolted to a splined hub the meshes with a steering shaft in order to transmit the torque from the driver to the wheels. Close to the bottom of the steering shaft, there is a pitman arm that is attached to the shaft to translate the rotational input into a linear output. Tie-rods are attached to the pitman arm in the center of the go-kart and connect to the spindles on the front left and front right side of the go-kart. All of these elements come together to control the steering of the go-kart.
2) Power Transmission
The torque for the go-kart is supplied by a 24 volt direct current 450 watt motor with an internal gear reduction transmission. From where the motor is mounted, a chain is wrapped around the motor sprocket and the axle sprocket, thus connecting the two and transmitting the motor’s torque to the axle.
3) Power Control System
The torque output from the motor will be controlled by the driver with a custom built pedal assembly. The pedal assembly will connect to an electric throttle which communicates the desired output to the motor, with the use of a motor controller. There will be a toggle switch mounted on a panel that will control the direction of the go-kart between forward and reverse.
4) Brake System
An electric brake, activated by a micro-switch in the pedal assembly, removes power supply to the motor. A separate brake pedal, connected to the brake drum by means of a cable, was included for additional brake control.
The fabrication process started with a 1.25 inch outer diameter, 16 gauge thick Hot Rolled Electric Welded steel tubing. The tubing was properly shaped with a bending tool, grinded, and welded to create the chassis of the go-kart. Reinforcement of the axle hangers occured with several passes of the welder. The steering shaft brackets and front spindles were also welded to the chassis. Mounting tabs for the floor, motor, and various covers have been cut from a sheet of 7 gauge steel and then welded to the chassis. Holes were drilled in both the floor panels and the mounting tabs to bolt down the floor securely. Electrical connections have been soldered for strength and protected with shrink wrap. The pedal assembly has been construction primarily out of aluminum and will flush mount to the floor with L-brackets. The chair mounted to the chassis, and the 4-point harness was bolted to the chair brackets.
In order to protect the frame from corrosion and outdoor environments, the decision was made to powder coat the frame. The powder coat color is a bright yellow, as it allows people to easily spot the go-kart from a distance. Electrical components housed within the confines of the frame needed protection from the elements as well. In order to protect the electrical components and for aesthetic purposes, fiberglass panels were fabricated as they allowed for custom fit and finish.
The go-kart was designed to travel at a walking speed and has been geared to travel at a top speed of 3.6 miles per hour. Power is supplied by two 12 volt batteries that drive a 450 watt motor.
When using an electric go-kart, it is important to know how far it can go on a single charge so that the occupant will not be stranded. Trail Runner tested the go-kart’s range and it can travel 16-18 miles or approximately five hours on a single charge.
Stability is vital for any vehicle operation. The go-kart can travel up an incline with ease as its lowest front to rear tipping angle is 31.9 degrees. Side to side tipping angles are 28 degrees, rendering the go-kart very stable. It has a turning radius of 6.5 feet.
The go-kart was designed to be easily transported and needed to be as compact as possible. The main means of transporting the go-kart will be in the back of Faith’s SUV. With an overall dimension of 54 inches in length, 36 inches wide, and 36 inches tall, it easily fits in the back of her SUV.
Go-Kart in Action
“The safety, durability, and overall functionality of the go-kart is really impressive. I cannot wait to hit the trails with Hunter and not be pushing him up the hill! WE LOVE IT!!”
Meet Trail Runner
Team Trail Runner is comprised of five Mechanical Engineering students of University of Nevada, Reno.
Gonzalo “Dragonfly” Barragan
Gonzalo Barragan moved to Reno three years ago to pursue a Bachelor degree in Mechanical Engineering at the University of Nevada, Reno. Outside of the academia environment, he likes to spend his time hiking, mountain biking, and does some landscape and light painting photography. He will be graduating in May 2014 and is looking forward to starting his career.
Alyx “the Lion” Colburn
Alyx was born and raised in Reno and grew up with a passion for all things outdoors. When not focusing on her academic career, she enjoys running marathons, hiking and skiing the beautiful Sierra Nevada mountains.
Justin “Muscle Man” Cross
Justin Cross moved to the Reno/Sparks area in 2008. Enthralled by cars, internal combustion engines, and all things performance driving, he chose to pursue a Mechanical Engineering degree at the University of Nevada, Reno. After graduation, Justin hopes to get a job in the automotive industry following his interests
Cody “Johnny Bravo” Macaulay
Cody Macaulay is a native Nevadan currently pursuing a Bachelor of Science degree in Mechanical Engineering at UNR. His studies at Truckee Meadows Community College resulted in Associate Degrees in both Drafting Technology and Engineering Emphasis. Gaining inspiration from different forms of transportation has encouraged Cody to continue in the direction of mechanical engineering.
Adair “Captain Jack Sparrow” Melendez
Adair Melendez will be receiving his Bachelor degree in Mechanical Engineering with a Minor in Renewable Energy this spring. Born and raised in Chile, Adair and his family moved to Reno, Nevada when he was just twelve. His background in designing and building energy systems will aid in the fabrication of the vehicle. Adair brings a technical background of energy storage as well as his understanding of manufacturing processes, which makes him a key component in the design and assembly of the electric go-kart. Adair’s enthusiasm for the project contributes to the camaraderie of the team.
Kolo 8 News- Engineering Students Show Off Projects
“RENO, NV – Some of the brightest students at the University of Nevada showed off their best work on Friday. For the last two semesters they have been working on projects that are so advanced, they would normally be handled by professionals. What they’ve come up with is pretty cool.” Article Link