Updated PDS

Over the last week, we have updated our PDS chart with more accurate metrics/requirements for our objectives and constraints. We realized the concrete values we had inputed into the PDS previously were not necessarily absolute requirements, but moreso goal values for what we would like our ideal final product to achieve. In addition to the updated metrics, we also added numerous new required functions for the reverse trike. Most are general functions of most forms of automobiles, but the addition of these functions more than doubled the size of our PDS. The PDS is as always a living document and further additional entries may be added in the future if we realize some crucial functionality is missing from our design.

We are also in the process of finalizing the front suspension components of the trike and our goal for the upcoming week (spring break) is to obtain them for mock-up. We have planned a group trip to the junkyard in order to see what we can get at a discount in order to reduce the final total price. The matter of what kinds of materials we can obtain in a timely and cost-efficient manner may end up being one of the major deciding factors for certain design choices we make for the final product such as suspension and type of metal used for the frame.

Below is the updated PDS chart with the adjusted metrics and added required functions:

Donor

Based on our requirements and strict budget we were able to find a power plant that meet our constraints and most of our objectives. We will be using a 95 BMW K1100 motorcycle for the engine, rear suspension, and electronics. A 98+ model would have been ideal since they have a reverse gear but that was out of the budget. They are similar in design so upgrading in the future is a likely possibility.

Market Research

One of the things we needed to do was establish what was already on the market to make sure we were not reproducing someone else's existing work. A google patent search pulled up a lot of information regarding tilting suspension  components or designs to bolt on new front suspension components to existing motorcycle chassis. Although there were a couple of designs that were similar in concept. One was for a motorcycle back half bolted to a formula chassis.Patent number: D449018

Polaris has a design that is more closely related to our designs style but it has very distinct functional, layout, and mechanical characteristics that separate it from our design. patents/US20120241237 They have a design which calls for a GM ecotec motor to be mounted  in the front section of the car and have a drive shaft to a differential which spins a cam and belt system. The design also calls for lots of stamped steel parts including the engine mounting/subframe assembly. Our vehicle will only share the exterior styling and the side by side two passenger arrangement. Our design will have a BMW motorcycle derived mid engine layout and will be shaft driven only. The engine mounting will be directly to the chassis with out the use of a subframe. We also plan on using as many parts bin items that are readily available in most salvage yards such as suspension components, seating, and electronics. 

There are several concepts on the internet that share a common design. They are all chain driven and use hand made suspension components. The reverse trike idea is pretty popular in Europe where most of the concepts and kits are available. The readily available kits however use parts and hardware that is not available in the United States. That is why we are going to use components from vehicles with global sales like the Mazda Miata and BMW K series. 

Concept Evaluation

                                   Engine                       Suspension

PDS

The following are the project design specifications for our vehicle (subject to change):