Overview of Requirements

Geometry

The geometry of our trailer involved a long group discussion. We looked at similar products and considered the opinions of people who have used bike trailers in the past. We found that the shorter and thinner we make the design, the safer and more agile it will be. 

When considering clearance from the ground, we used the standardized sizes of bike tires. The higher the load is kept, the higher the center of gravity which is not good for stability. We chose smaller tires similar to other trailers which would range from 6" minimum to 12" maximum. a good amount of clearance is necessary while off the road as small obstacles on the ground would otherwise create problems.

Kinematics

Many competing products have an option for suspension at an elevated cost. We believe suspension is a definite requirement to provide a safe and comfortable ride for our consumers.

Forces

The forces acting on our trailer is a big topic and can be discussed for days. To provide a brief overview we will only consider the main forces acting on our trailer. The trailer's load should not exceed 100lbs. While the material making up the structure can support more weight, we want to provide a significant factor of safety for our consumers. It is also important to note that the consumer will have to tow this trailer via their own power and probably cannot travel long distances with a load exceeding 100lbs.

Later this month we should have optimization results from a project we are doing in our CAD/CAM class. This project involves stress analysis of a 3D model of an existing trailer. We will post those results soon!

Energy

We would like our bike trailer to address some of the concerns of our prospective consumers. One of the main issues for people traveling long distances or in off-road camping type locations is the fact that they cannot charge their small electronic devices. We would like to include a means of converting energy from the trailer in motion into electrical energy that is either immediately used and/or stored and used later. The minimum requirement is the ability to charge a small electronic device such as a cell phone or GPS unit at least once over the coarse of riding for one day.

Material

There are many options for materials used in this design. Because of the volatile nature of the outdoors everything must be corrosion resistant. We require that the items stored on/within the trailer are also protected from the surrounding environment and weather. Also, all electronics including the container surrounding the energy generating element and consumer devices must be waterproof.

The materials used in the trailer's structure should be weldable and machinable otherwise production and cost would be too high.

Safety & Ergonomics

There are many aspects of our design that incorporate safety and ergonomics. Our group briefly mentioned brake lights, turn signals, torsion control (single wheel), and a quick release mechanism as wishes that are not necessary. Many of the above items can be purchased and installed later and would only increase our overall cost.

Some other aspects we deemed as demands which include a maximum speed rating of 50mph, a narrow body for agility and safe street use, an easy mechanism for connecting the trailer to a bike's rear axle, and finally an environmentally friendly final product design.

Production

We will eventually come to the point where we decide if we actually want to market our design as a real product. If and when that happens we will need to organize our design in a way that allows for mass production in a cost effective way. Not only that but we must also perform many tests like load bearing tests and fatigue and usage tests. There is also the possibility of needing permits and certifications for our product since it will more than likely be used on public roadways and other government regulated property.

Assembly

As of now we have not progressed far enough to finalize our trailer's structure. We can only speculate that we will either manufacture our trailer to be one piece, multiple connectable parts, or something that needs to be fully assembled. It seems like a reasonable  assumption that one piece will provide a more structurally sound product while something that needs to be assembled provides a method for portability and convenient storage but also more maintenance.

Operation

We already know most of our consumer demographic and we know that we want our trailer to fit their traveling needs including the option for rugged and off-road terrain. The demographics that match our expectations are as follows: Environmentalist,  Conservationist,  Active Lifestyle, and Travel demographic.

Maintenance

We agreed that while maintenance is an important factor of design, we must progress further before knowing what will and should be required for maintenance. The only aspects of maintenance we have come up with to date is rust, wear and tear, and if we include other parts they would have their own respective maintenance responsibilities.

Recycling

As we want our trailer to be environmentally friendly we would like to incorporate materials that can easily be recycled and/or reused. From a production standpoint we would like to be able to reuse material that is extra and/or defective. From the consumer's point of view we want them to be able to easily dispose of the product after its life and demonstrate the environmentally friendly nature of our product.

Costs

The cost of similar competing products is around $380. This price point only includes features like the trailer frame, a waterproof bag for storing the load, and  a suspension. The maximum load is only around 70lbs.

We would like to design a competitive product that is either cheaper with the same or better functionality or more expensive but with added features that justify the additional cost.

Schedule

We plan to have our bike trailer fully designed and have a working prototype by April of 2014 which is near the end of our last semester - Spring 2014.