Introduction¶

Your team will be tasked with developing a design to meet a hypothetical need for Unitrans, the public transportation system in Davis. Davis is known as the "Bicycle Capital of the United States" and Unitrans finally wants to figure out how to carry bicycles on their buses like many other transit authorities in the country [1]. Your team's job will be to develop a detailed mechanical design for a dual bicycle rack that is mounted to the front of a typical Unitrans bus. The design will have to meet a number of constraints and have a variety of features, all while being safe, easy to operate, easy to maintain, and be cost effective.

Learning Objectives¶

• Students will be able to design a complex mechanical system.
• Students will demonstrate the effective use of engineering analyses to guide design decisions in an open-ended problem.
• Students will develop team work and collaboration skills to support a technical mission.
• Students will be able to describe their design using verbal, written, and graphical communication means.

Project Goals¶

• To collectively develop an open ended mechanical design that meets static/dynamic failure criteria while meeting the client's needs.
• To perform detailed static and dynamic failure analyses for your design to prove that your design meets all requirements and is safe for consumer use. You will need to report an overall factor of safety that should be appropriate for this type of product.
• You will need to estimate the cost of manufacture and report an estimated "Manufacturers Suggest Retail Price (MSRP)" price for the design.
• Log your design activities in your design notebook or in electronic documents and keep you materials well organized.
• Include any pertinent information that you find during your research.

Design Needs¶

• The bicycle rack must be able to carry at least two normal bicycles (wheel size 20" to 29", road and mountain width tire tread). The maximum weight of a single bike shall be no more than 55 lbs. It will not accommodate non-standard cycles like unicycles, tandems, recumbents, etc.
• The rack should be able to hold a static load of 250 lbs, e.g. a person should be able to stand on it while washing the window.
• The rack must be attached to the front bumper area of the chassis.
• The bicycles must be guaranteed not to fall off during transit.
• It must be usable by a variety of people and allow for the easiest possible bicycle attachment to the rack.
• The bicycles can not be damaged in any way by the rack.
• The footprint of the rack should be as small as possible while meeting other design needs.
• The rack must be manufactured using traditional manufacturing techniques and made of standard steel or aluminum structural elements.
• The rack must be corrosion resistant and designed for an all-weather environment.
• Each bicycle must be able to be loaded independently.
• The rack design should never force the user to be on the traffic side of the bus to load/unload the bicycle.
• The operation should be intuitively obvious or clear simple instructions provided on or near the rack.
• The rack itself should weigh no more than 75 lbs and be removable.
• The rack should not protrude past the sides of the bus.

Obtaining Information¶

Destiny and Jason will act as the project supervisors who are in direct contact with the stakeholder (Unitrans). To obtain information from the stakeholder or to find out information that isn't discoverable in your research you will ask your questions through Piazza. Your questions need to be professional, clearly communicated, and pointed. They should be written in format, tone, language that you'd expect to see in professional communication. With good questions we will provide you with the needed information to clarify the details. But, keep in mind that there may not always be an answer and it is up to your team to make the best decisions with the available information. Ask early and often!

Activities¶

Memos and Reports¶

You will create four memos and a final report. The reports will all be turned in as PDFs to Canvas on the respective due date by 5pm. Each memo should stand on its own and you will be able to use the content as a base to develop the final report.

• Each report or memo must be submitted as a single PDF document.
• Your group is free to use any software you prefer to prepare the documents.
• The memos and report should be treated as professional documents and should be self contained.
• The audience you should write for is a technically competent reader, e.g. another engineering colleague or engineering management.

Lightning Talk¶

Your team will have 5 minutes to pitch your design. The talk will be followed by 5 minutes of questions while the next team sets up. The intended audience for your pitch will be engineering management and a potential purchaser of the product, so adjust your content appropriately. You should touch on the design features, analyses for failure, manufacturing and cost, etc. One person will be selected randomly from each group to give the talk. This means that everyone has to prepare to give the talk and it is in you best interest to help each other practice.

Suggestion:

• Make ten slides that will be shown for 30 seconds each (each team member makes 2-3 slides).
• Each slide has an accompanying script that focuses on the main points.
• Make sure your computer works with the TV in the design studio (Bainer 2071).

Notes:

• We will be very strict with time. You will be cut off at 5 minutes!
• Can use visuals: board or TV
• It takes more time than you expect to make it concise!
• Your grade will come from the participating judges.
• The best talk, based on class vote, will get a prize!
• https://en.wikipedia.org/wiki/Lightning_talk
• Giving a good lightning talk
• 16 ways to prepare for a lightning talk
• Search for "Lightning Talk" to find many other resources.

Grading¶

The individual grade for the final project will be broken up as such:

The peer evaluations will be used to scale your project grade based on you and your teams ratings.