As Thanksgiving approaches and all the Uncles, Cousins, and Aunts are assembling, the task of inserting the leaves in the dining room table looms large. Typically, the table leaves are stored in some forgotten location, and when found have to be carried to the table and manually placed in it. Wouldn’t it be better if the leaves (leaf) were stored within the table itself and were automatically inserted into place when the table was opened? Our marketing mavens think that there is demand for such a Dining-Table Leaf Insertion Device. Our marketing survey data seem to indicate that few such devices are currently on the market.

    The only constraints imposed on the problem are that the device must be simple to use, preferably using the action of opening the table-halves as the actuating motion. That is, as you pull the table open, the stored leaf should be carried by the mechanism of your design into its proper place in order to extend the dining surface. Thus, a linkage solution with manual input is desired and full joints are preferred to half joints, though either may be used. Remember that simplicity is one mark of good design.

    We want some creative preliminary designs which show promise for further development. 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 does work!). Also read Chapter 18 for some additional insight into the design process.

    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 expect to typically 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 degree 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 us how you arrived at it, including the failures encountered along the way. This will demonstrate to us 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 or with similar motions.

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

4. Review the position synthesis sections of your text.

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

5. Cardboard models make designing much easier.

IMPORTANT! IMPORTANT!