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Revision as of 14:13, 12 October 2007

Market Research

Difficulty applying pressure

Tool too long to access screw

Difficulty from an angle

Bit connection problems

We asked a number of people to use a ratcheting and non-ratcheting screwdriver on a variety of normal household items. The items tested included a CD player, a towel holder, chairs, a fan, a bedframe, a vaccum cleaner, and an airsoft gun. The idea was to provide a wide array of objects and a large sample size in order to gain a new perspective on how people use the tools and the problems they often encounter.

After carefully observing each of the users and interviewing them about their experiences afterwards, the most common problems experienced were:

1. Applying ample pressure
2. Screwing from an angle
3. Determining which way the screwdriver is set up to ratchet
4. Screwdriver being too long to access a screw
5. Screwdriver being too short to access a screw
6. Bit connection is unstable
7. Bit connection point is too thick to access a screw
8. Stripping screws
9. Lighting issues
10. Difficulties with nut/bolts

Project Schedule

The schedule for the remaining part of the project is layed out in the Gantt chart below. The milestones' occurences are denoted by a yellow triangle and have a breif description next to them. The big milestones will be the completion of Prototype 1 and Prototype 2, the Final Report, and the Design Expo. The chart is in one week increments with the red parts of the bar denoting the parts of teach task that have been completed and the cream-colored yellow represents the time remaining to complete the task. All tasks will initially be completed as a group, and will be divided up as seen fit when we are doing tasks.

Gantt Chart

Design Analysis

Pugh Chart

Value Opportunity Analysis

Aesthetics

Core Technology

Emotion

Ergonomics

Identity

Impact

Quality

Final Design

Market research has shown some issues with the current design of a ratcheting screwdriver. Our proposed choice of redesigns consists of several key features meant to improve upon the original design. The new design will be easier to use, the controls will be more intuitive, and more versatile than the previous design.

The first feature being redesigned is the handle. The existing design, while tried and true, has several flaws. Gripping the handle requires an unatural hand position and quickly leads to fatigue after repeated use. The new design is much more ergonomic. The pistol grip is a much more natural postion and since the device is not operated by a twisting motion the probability of fatigue is greatly reduced. The new handle design also promotes the use of downward pressure and will therefore reduce the number of stripped screw heads.

Included with this new handle design is a new operating mechanism.

Clearly illustrated switch One hand switch operation Rotating

Hand powered Trigger

loose screw

storage for bits