The Trike-Me tricycle is designed around the specifications from our sponsor. It offers an alternative mode of transportation compared to traditional tricycles. The sponsor wanted a tricycle that had sleek design with clean lines with no controls constantly rotating on the hand cranks.
Our design uses hand pedals to propel the tricycle forwards and the steering is accomplished with the use of foot pedals. The configuration of the tricycle is a recumbent design, meaning that the rider’s body is oriented in a horizontal position. When a rider presses down on one pedal, the tricycle will turn in that direction. To allow for different terrains, the tricycle uses an internal geared hub. The hub has nine different gears that increase or reduce the gear ratio with the use of the shifter located next to the rider. Additionally, there are brakes located next to the seat. There is one brake on each side of the rider. The brakes are separate system designed as a failsafe in the unfortunate event one brake fails. The tricycle has necessary lights and reflectors to meet safety regulation. These lights also aid in visibility not only for the rider, but also for other vehicles on the road.
To design the tricycle, the group met with the sponsor and recorded the items the sponsor wanted. The sponsor included details about why nothing on the market worked for him as well as some items he would like to see in the final product. From there we were started the long procession of designing. The first designs were simple hand drawings while the final drawings were done with Solidworks. Once we found a design that worked, we started making the product. The finished project reflects the drawing relatively well.
The sponsor of the project had specifications that he wanted the finished product to be able to complete. The purpose of Phase I (Design Inputs) is to get an idea of what the customer wants. The most important specifications for the tricycle, was that it needed to be hand powered. This was one specification that did not change throughout the project. Another specification that did not change was disc brakes on the rear of the tricycle. A large portion of the specifications changed as the sponsor changed his mind. He finally settled on a steering system that was controlled with his feet. Other specifications were selected in a compare and contrast order. The sponsor wanted different gears for the tricycle, but did not like how the common gear system looked. We settled the problem with the use of an internal geared hub. Other aspects of the tricycle were decided by the group, picking the best item or product for the job.
The tricycle market is a diverse market. The market has a high-end and low-end; with everywhere in between. There is one problem with most tricycles; the controls are cluttered. The market for our design is small. The design is limited to people who do not enjoy pedaling with their feet but still want foot controls.
The design output falls under Phase II. The purpose of this phase is to document the progress of the project as well as ensure that the project is meeting the required specifications from Phase I.
Verification and Validation
The purpose of verification and validation (Phase III) is to verify that the design outputs from Phase II are being met. Some aspects of the project can be confirmed by checking the drawing of said part, while others will need to be confirmed through testing.
Testing the tricycle was an easy task. The first order of testing was the brakes. The initial test was done by lifting each wheel with a brake mounted to it and spinning them. This not only allowed for less risk in checking the function of the brakes, but also allowed us to check to see if anything was there that could cause damage to the moving parts. After we did a brake test, we checked the steering. The steering was checked by ensuring that the wheels turned as much as the design would allow. Once the steering and the brakes were tested, the drive system was tested. The hub needed minute cable adjustment for it to shift correctly. This was anticipated so it did not cause any problems. After the initial tests were done, the group rode the tricycle for an all systems test. This test included braking, turning at high speeds, up and down hill and anything else in between. The test performed as anticipated. Turning at high speeds can be problematic, the brakes were easy to reach and had great stopping power, and the internal geared hub allow for reduce effort in climbing hills. The group was able to verify or validate each project requirement.
The purpose of Phase IV is to make the design that the group has been working on as is past Phase: l, ll, lll. This included building the prototype as well as design packaging and other items need to sell a product. For our group, we do not intend on making anymore tricycles than the one currently built. The manufacture process was a fairly common build. It was very important to line everything up so there would be no flaws in performance for the final product. To prevent errors in the build, measuring was done multiple times.
The first step of the process was to cut the metal to the desired length. We started with the frame and slowly built our way up from there. The frame was welded in a “T” pattern then the hand crank holder was added to the frame. The next step was to drill holes for the seat. To accomplish this, we made a template for the holes in the bottom of the seat out of cardboard and transferred the data from the seat to the frame. After we had the holes marked, we drilled the holes. The next step of the build was to weld the c-knuckles onto the frame and the drop outs for the front wheel. After this the frame was done.
The next order of business was to make the steering spindles. This was done by bending a tube and welding a tab on it for the steering linkage. A piece was also added for brake mounting. The steering linkage was made by welding a nut into the end of a tube to allow for the heim joint. The next step was the foot pedals, which were cut to the specified lengths and welded together. After this is it just need paint and part assembly. The wheels need the spokes and nipples installed and so did every other part.
The tricycle was a success. The future of this project currently does not exist, but there could be improvements made to the design. Heavy negatively caster could possibly aid the tricycle in self-centering the wheels. Currently the steering design has to be manually controlled, which noted on innovation day, a small percentage of riders had an issue. The problem can also be resolved with more practice. We believe that the adjustment of the steering angles could aid in making the rear steering design as functional as possible. If there were a later design, it would incorporate front steering and rear wheel drive, opposite of current set up. Overall the steering works great considered the limitations of the rear steering requested by the sponsor. The group feels like human powered alternatives could be used instead of current golf and utility carts. Companies and other governing bodies would probably prefer this because of a lower maintenance cost and with the possibility of better health benefits. Overall the tricycle is a fun design; a large number, if not all of the people who rode it were pleased.
Meet the Team
Mark Lanski is a transfer student from Antelope Valley College in Lancaster, CA. He started attending UNR in Fall 2013 and is planning to graduate Spring 2016 with degree in Mechanical Engineering. He enjoys riding mountain bikes and motorcycles, shooting, reloading, fishing, numerous sports and the list goes on. He hopes to get a job that he can truly enjoy.
Mike Lanski will be graduating Spring 2016. He is currently looking a job for an entry level engineer.
Kevin is a mechanical engineer who is currently a full time student at UNR as well as a full time employee of Reno Sub Systems. He looks forward to helping advance the world through his work using the knowledge he has gained through his education and experience in the workforce.