The Adjustable All-Season Stroller is a cost effective adult stroller that has been designed by High Roller’s Stroller. The seat adjustability mechanism in the stroller has been designed to comfortably accommodate passengers up to 5′ – 5’6″ tall, and the ski attachment mechanism allows any generic stroller to be attached to the skis such that it can be used in a snow suffused environment.
Congenital Disorder of Glycosylation (CDG) syndrome is a disease that results in mental and physical disability by hindering the Glycosylation of proteins and lipids in an individual. Hunter Yeider is a 16 year old boy who has been affected by CDG – Type I since birth, and this has affected muscle growth in his body. Hunter lives in Truckee, California with his mother Faith Yeider. Committed to help people with disabilities and make a difference, HRS met with Faith and Hunter in 2012 to discuss engineering problems that they encountered in their daily life. That meeting helped HRS identify the two design problems that it wanted to tackle:
Lack of seat adjustability mechanism
Hunter’s height (5’6″) and lean built (86 lbs) require that a seat adjustment mechanism is built which will allow his stroller to comfortably accomodate him
Unavailability of cost effective solutions to make a stroller snow maneuverable
Truckee is covered in snow more than six months during a year. Hunter’s current stroller cannot be used in snow and there are no cost effective solutions available to this problem.
To read Hunter’s story and learn more about him, click here.
The Adjustable All-Season Stroller is a cost effective adult stroller that has been designed by High Roller Stroller. HRS started this senior design project in Fall 2012 for senior capstone class. The team comprises of five senior mechanical engineering students who have been determined to deliver a project that impacts the lives of people in a positive way. HRS’s journey over the past year can primarily be divided into four steps:
Identifying design constraints
Leah Southern, one of High Roller Stroller’s team member, introduced the team to Faith Yeider in September of 2012. HRS traveled to Truckee, California to meet Faith and discuss the possibility of working with her to solve one of the engineering problems that Hunter encounters in his daily life. After meeting with Faith, HRS realized that it could help Hunter and Faith with more than one problem:
Increasing the comfort level provided by the stroller: Seat adjustment mechanism
Hunter has been affected by Type-1A CDG syndrome since birth and this has affected his body’s ability to grow muscles. Hunter is 16 years old, 5’6″ tall but only weighs 86 lbs. The adult strollers that are available in the market these days are either too big or too expensive.
Unavailability of cost effective solutions to make a stroller snow maneuverable: Ski Attachment Mechanism
It is imperative for Hunter’s physical growth that he spends time in outdoor environments. However, lack of cost effective solutions to make a stroller snow maneuverable have been a problem.
As HRS talked to Faith about the engineering design problems that Hunter encountered in his daily life, HRS took note of the important factors that it wanted to address in its design. HRS came up with three primary design constraints (DFX):
Ergonomics: Improper seating posture is detrimental for Hunters growth. It is imperative that the stroller that Hunter uses comfortably adjusts him, and helps him maintain a good seating posture. HRS had to come up with a design that would facilitate Hunter’s growth and help him comfortably enjoy his ride in the stroller.
Design for safety: Reliability and durability are very important for Hunter’s safity because of his inability to stabilize himself. HRS had to ensure that the material it was using to fabricate the seat adjustment and ski attachment mechanisms was strong, and as a result Aluminum was chosen for its final product.
Design for cost: After talking to Faith, HRS had realized that it was essential that the stroller design was within the scope of a middle class family’s budget. Cost has been a very important through HRS’s design process, and impacted HRS’s decision to not use its proof of concept design for the ski attachment mechanism.
HRS designed a ski cambering mechanism in Fall 2012 as a solution to make the stroller snow maneuverable. To test the effectiveness of this design, it constructed a quarter scale model using erector set parts and nylon blocks milled into skis. The mounting pins showed in the picture below, allowed HRS to test the performance of proof of concept for different configurations of the cambering mechanism.
HRS tested the turning ability of the cambering mechanism as compared to a non-cambering mechanism. The cambering mechanism was able to reduce the turning radius of the stroller by about 25%.
The proof of concept helped HRS realize that even though the proof of concept improved the turning ability of the stroller, it was not a cost effective solution. The quarter scale model costed HRS about $70, and the project cost of the full scale model was about $200.
After the proof of concept was analyzed, it was determined that a non cambering mechanism will be used for the ski attachment. At the same, the team had also design a seat adjustment mechanism that would comfortably accommodate Hunter. The ski attachment and seat adjustment mechanisms have been discussed here.
“The superior performance and portability of the stroller has opened up a whole new world for Hunter and I”
Ski Attachment Mechanism
To facilitate with Hunter’s developmental health, it is important that he spends time outdoors as much as possible. Unfortunately, Truckee is covered in snow more than six months out of every year. This makes it very difficult for Hunter to get the physical and mental stimulation he needs. To solve this problem, HRS has developed a mechanism that will latch on to the bottom axles of the stroller Hunter will be using. To use this mechanism, the user simply needs to unclip the stroller wheels from the stroller’s axles, and then snap the axles into the gate latches on the ski attachment mechanism.
HRS tested the ski attachment mechanism and it seems to be working great. The process of attaching/detaching the skis takes about 40 seconds to complete, and does not require a great deal of physical strain on the part of the user. Here is a video explaining how the ski attachment mechanism works:
Seat Adjustment Mechanism
Because of his disability, Hunter’s frame is not large enough to fill an adult stroller safely, but it is too large to fit into a child’s stroller comfortably. For this reason, HRS has developed a custom seat for Hunter that not only fits hit current height and weight, but will adjust to allow additionally room as he grows. Using this mechanism, the angle between Hunter’s lower and upper legs will always be more than 90 degrees, and it will comfortably accommodate him.
The seat adjustment mechanism has been designed to ensure that it does interfere with the portability of the stroller. The stroller can still be folded and stowed away conveniently. Faith and Hunter tested the stroller for a week before HRS could make final design adjustments for project submission. Hunter loves how comfortable the stroller is for him, and Faith the ease with which she was able to handle the stroller.
Here is a video showing how the seat adjustment mechanism works:
HRS gave the stroller to Faith to test it for a week before the project submission. HRS requested Faith to fill out a survey that had been prepared to see what all improvements could be made to the design or what similar problems could be tackled by design teams in future. To see Faith’s response click here.
Meet the HRS team**********************
Team High Roller Stroller comprises of five Mechanical Engineering students of the University of Nevada, Reno. The strength of the team HRS rests in each member’s belief to work towards humanitarian causes, and impact lives of people around the world.
Hunter loved the group so much that he gave everyone nicknames.
Connor ‘Slam Bam’ Warren
Connor was born and raised in Reno, NV. He will be graduating in may of 2013 with a degree in Mechanical Engineering. Previous mechanical experience includes working as an intern in energy generation at a power company and being the family mechanic. When he is not busy studying or doing homework, which he does quite frequently, he likes to spend his time outdoors mountain biking, whitewater kayaking, backpacking, etc. When he graduates, he is leaving to fight wildfires in california and hopes to eventually work as a firefighter for a city department.
Jake ‘Flameslinger’ Holland
Jake Holland is the team captain of High Roller Stroller. Originally from northern California, he will be graduating with a degree in Mechanical Engineering. Currently he is an intern with PCC Structural in Carson City, Nevada. On his spare time Jake races stock cars at different locations across the western United States giving him hands on experience needed for the project. After graduation he plans to pursue a full time position in industry in the Reno area.
Joe ‘Ignitor’ Rinaldi
Joe Rinaldi went to Galena High school. He graduated when he was 15, and began studying engineering at UNR. He has always been interested in engineering, and specifically chose mechanical because he had done some projects with it, and it sounded like fun at the time. After graduation Joe will most likely go into industry, though he has not chosen a specific career path at this point in time.
Ketan ‘Crusher’ Mittal
Ketan Mittal moved to Reno three years ago to pursue a bachelors degree at the University of Nevada, Reno. Motivated by his brother, and intrigued by numerous mechanical devices that he observed in daily life, he chose mechanical engineering. Ketan Mittal has been working as an undergraduate research assistant with Dr. Miles Greiner at UNR. Ketan has interest in heat transfer and controls. He also worked with Dr. Kam Leang at UNR to develop a quadrotor with autonomous control and ultrasonic sensor stabilization control. He plans on going to graduate school after he graduates.
Leah ‘Ninjini’ Southern
Leah Southern has been in the Reno/Sparks, NV area for the past ten years and got an early start on college by attending Truckee Meadows Community College High School. Following the advice of a music teacher, she began a college career in the pursuit of a degree in Mechanical Engineering. She will be graduating in May 2013 with a Bachelor of Science in Mechanical Engineering and couldn’t be more thrilled to start her career this summer. She has known the Yeider Family for over ten years and has watched Hunter’s incredible development despite his rare disease. Giving back to such a unique individual has been a huge highlight in Leah’s college career.