A paraplegic client has hired us to design a mechanism that he can have installed on his new 3-door ‘97 Ford F150 Super Cab Pickup Truck and which will allow him to store his wheelchair in the area behind the driver’s seat. He has excellent upper body strength and, with the aid of specially-installed handles on the truck, can pull himself up into the cab from his chair. He wants your mechanism to lift his folded chair up into the storage area behind the seat. He can fold the chair and attach it to your mechanism which should then automatically lift it and place it in the truck. The truck can be modified as necessary to accommodate this task. For example, attachment points can be added to its structure and the back seat of the truck can be removed if necessary.

    We want you to generate some creative preliminary designs to solve this problem. The section titled A Design Process in Chapter 1 will help you to get started and guide you to potential solutions. Please read it carefully. (It really works!). Also read Chapter 18 for some additional insight into the design process.

    The only constraints imposed on the problem are that the device must be stable, effective and safe to the operator. Full joints are preferred to half joints and simplicity is the mark of good design. A linkage solution with motorized input is desired, though flexible links and gears are also allowed. A wheelchair will be provided for your inspection.

    You must follow the Design Process to fully define and constrain the problem. You must do Background Research into the problem and any existing solutions. You must create a general Goal Statement. You must generate a list of at least 15 Task Specifications. As with any design problem, there is an infinity of solutions possible. You are expected to come up with one solution which will work. To do so you will have to try out many alternate designs and iterate to your 'best' solution. You should typically expect to go through at least ten iterations before arriving at an acceptable one.

    There will not be a need for extensive analysis in this project as it is a preliminary design concept study. However you are expected to do a "first order analysis" to determine the feasibility of your design. This must include, at a minimum, analysis of the degrees of freedom of your design, its Grashof condition (if applicable), the input force or torque required over the range of motion, the minimum transmission angles, the mechanical advantage, and any other parameters you think important.

    You are also required to document your solution in a professional engineering report which adheres to the Project Report Specifications document supplied. (Ask for a copy if you don’t yet have one.) This report will document the process by which you iterated to your final design as well as document the design. Do not just describe the final result. Rather show me how you arrived at it, including the failures encountered along the way. This will demonstrate to me that you understand the engineering concepts and the relevant course material. A working cardboard model of at least one plane (one side) of your design is required.

Some suggestions to get you started:

1. Do research before trying to solve the problem! Don't 'shoot from the hip'. Avoid BFI.* Engineer it.

2. Try to find information on existing products of a similar nature. Go look at the truck and measure it.

3. Investigate the user's needs and abilities (human factors). Interview potential users.

4. Mr. Hrones and Mr. Nelson might help.

5. Cardboard models make designing much easier.

IMPORTANT! IMPORTANT!