A Case Study of the ARRIS Design
ARRIS is a computerized medical imaging system developed at Robert Q. Riley Enterprises, LLC. It won the NewMedia Gold Award (End User Category) and Award of Excellence.
An award-winning design rarely emerges from good mechanical design or esthetics alone. More often, it is the result of overall design integrity, or the way in which form and function are packaged to convey a consistent message. An appearance model or mockup serves to verify the product’s ergonomics, and also to prove out the design’s visual statement.
ARRIS, the product shown in the photos, is a computerized medical imaging system oriented primarily toward the chiropractic field. It provides a more precise method of measuring and documenting skeletal abnormalities and misalignments. The product consists mainly of a video camera, a personal computer system, a set of load cells to sense weight and center-of-gravity, and the software necessary to integrate the subsystems, analyze the data, and provide an operator interface.
To perform a basic analysis, the patient stands on a large disc which slowly rotates through three-quarters of a revolution while a video camera sends images to the computer. When the scan is finished, images of the patient are displayed on the unit’s built-in monitor where the operator enters anatomical points. In addition to side, front, and rear video images, the computer also constructs an overhead view of the patient. After analyzing the graphical data and integrating center-of-gravity information from load cells under the disc, the software then produces a report that includes an image of the patient with a graphic overlay and a narrative with highlighted abnormalities. Other capabilities include range-of-motion analysis and video analysis of X-ray films. Virtually any anatomical characteristic that can be visually detected can now be quantified, analyzed, and compared to normative criteria in the computer’s memory. Current scans can also be compared to prior scans in order to document the effectiveness of treatment.
Although correct software architecture and good mechanical design were essential, a number of marketing issues were critical to the product’s success. The primary challenge centered on the high development costs in contrast with the comparatively narrow market, which implied a relatively high selling price. A preliminary study indicated that ARRIS would cost somewhat more than competitive systems using older technology. Consequently, an important objective of the product’s design was to elevate its perceived value and give the product a quality, high-tech appearance consistent with its price and function.
As is typical, initial design selection was based on renderings. Renderings, however, can imbue a design with qualities that may not necessarily come through in the actual product. To avoid the pitfalls of artistic representation, full-size appearance models are necessary in order to prove out candidate designs. Appearance models demonstrate the product’s visual impact, and in addition, they also verify the ergonomics of the design. An appearance model need not be especially costly. Much depends on the complexity and size of the design, the necessary structural strength, and the amount of detailing needed to accurately convey the look and feel of the product.
With ARRIS, two models were built of polystyrene foam. Detailing was kept to a minimum in order to save on expenses. The images here show the foam appearance model that was selected as the final design, the first-generation prototype, and the monitor’s primary workspace.
The inventor’s vision was that the subject would stand on the disc while a camera took digital photos in three rotational positions as the disc slowly rotated into each position and paused. The operator would then use a laser pen to input points on the image. Software would then generate vertical and horizontal lines to show postural abnormalities. Software would construct an overhead view as well. The radar-like pattern on the disc was used to locate the subject’s feet. Feet could not be restrained due to loss of balance hazards. Load cells under the disc determined whether the subject was favoring one leg. The rectangular objects at the end of the outriggers are removed to reveal adjustment knobs for leveling the device. The column at the left in the mages contains a standard PC. Click on the following images to get larger versions.