2D and Solid Modeling Speeds Design of Heart Rate Monitor Watch

When Sports Instruments of Park City, UT, decided to manufacture a new heart rate monitor watch, they hired Tres Design Group, Chicago, IL, to produce the design. This product, called the ECG Series, was to display an athlete's heart rate during exercise, plus feature a timer, chronometer, time of day, date, settings for upper and lower heart rate limits, and a lap counter. Sensors embedded in an elastic band would be worn around the athlete's chest, with the negative and positive poles of the sensors picking up the heart rhythm. The rate would then be transmitted by radio frequency to a coil inside the watch, and converted to data for an LCD display. A big challenge in designing the watch would be to make the numbers easy to read.

Design began by taking the list of electronic components the watch would contain and drawing them in 2D, then assembling them onscreen to create the most compact package possible. Preliminary design for the LCD display also occurred at this time. Designing a display involves resolving how much room will be needed to present all the information, the sequence in which the information should appear, the relative sizes of the different rows of information, and other related considerations. It was necessary to make these decisions early because they determined the size of the LCD, which then dictates how much battery power it would require, therefore defining battery size and location within the internal electronic module.

Since the 2D layouts were created with Vellum Solids from Ashlar, Santa Clara, CA, it was easy to extrude the forms into solid models. Details could then be further sculpted into the watch face, such as the opening for the LCD display and the ports for the keys. All files could then be saved into .STL files for the production of rapid prototypes, and the final details were saved back into the 2D files for use in production tooling control.

For more information:

Circle 430 - Tres Design Group, Inc.

Circle 431 - Ashlar Incorporated or connect directly to their website via the Online Reader Service Program at http://www.1rs.com/005df-431