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Freetech Wins Top Thermoforming Award For Second Time In Four Years

Freetech has again won top awards in Thermoforming receiving both the Best Medical Enclosure, and the Peoples Choice Awards at the 1999 Thermoforming Conference for Intuitive Surgical's Da Vinci Robotic Surgical Workstation.

The Da Vinci Robotic Surgical Workstation has already won numerous other awards for design Including Appliance Magazine "Excellence In Design Competition", ID Magazine Annual Design Review "Design Distinction Award", Cannon Communications "Excellence In Medical Design Awards", an an award from The Chicago Museum of Modern Art. Winning the top award for Thermoforming emphasizes just how special this product really is and the tremendous effort that went in to making it.

Freetech's technological advancements in The West Coast Style of Pressure Forming made the dramatic look of this design possible.

West Coast Style Thermoforming has grown up around the industrial design community in California. The design community’s demand for new and exciting product looks not usually seen in this process created a demand for someone to stretch the Pressure Forming envelope. These products required matching several different components from varied processes such as sheet metal, RIM, and Pressure Forming into a single product. The components usually ended up being painted so it meant molded in color and texture weren’t mandatory. This allowed Designers and Pressure Formers willing to work with them much more freedom in their approach to product shaping allowing far greater creativity, and more exciting designs could be brought to market.

This was coupled with product runs of around 500 to 1,000 units per year, on higher ticket items such as medical, scientific, telecommunications equipment. New shapes not formerly associated with Pressure Forming such as tall and narrow ventilation ribs with no draft and deep undercuts to accommodate hardware and sheet metal interface requirements began showing up. As designers added more daring design features thermoforming enabled these bold new looks to be practical in lower volume products. This resulted in the West Coast style of thermoforming emerging to keep up with these new product demands.

This whole process has came together to produce the bold futuristic look of the Intuitive Surgical's Da Vinci Robotic Surgical Workstation. It required intense and extensive collaboration between Lunar Design, Intuitive Surgical, and Freetech over about an 18-month period. Many of the Da Vinci enclosure’s features had been done individually on prior programs but nobody ever put together so many technologically demanding shapes and features into one package. Additionally the fact there would be no square or perpendicular features for part fixturing or locating just added to the difficulty level.

Using the best basic processes for low volume products The Da Vinci console uses an cast aluminum base and tubular frame with a sheet metal infrastructure. Pressure Forming was used for all the exterior covers as no other process was practical or economical for achieving these shapes in parts of this size. Once formed trimmed and painted the Pressure Formed covers are aligned to the frame using ball studs mounted onto precision 3D machined locating pads to assure that the free form organic shapes of the individual covers locate accurately into their assigned places.

The upper left and right cosmetic panels also help enclose the surgical controls. Since the surgical console can be used to perform long complex operations, a return radius was formed on all edges on the inside of the covers. This achieved a smooth ergonomic and finished look rather than having a machined edge. This eliminated sharp corners the surgeon could possibly encounter multiple times during a long procedure while keeping the surgical controls isolated.

The top rear cover had to maintain a uniform wall thickness in order to match up with the rear power supply covers and the 2 side work area enclosure covers as well as the top viewer cover. In order to achieve this, the slip sheet-forming process was used with a 3D- machined matched metal tool. This actually was more economical than using a mold with pneumatic slides to produce the same kind of finished edge in a typical pressure formed part.

The top viewer cover had to provide not only for a highly aesthetic appearance but interface ergonomically with the surgeon. It also had to cover duel medical monitors and the other electronics that provided for the 3D image that the doctor would see. The safety interfaces that would insure the surgical arms were only operative if the surgeon was looking thorough the viewer were molded into the deep recess in the covers center. The resulting 3D negative draft geometry draft as well as positive features on the tool, required an extremely complex removable insert in what was already an extremely difficult tool. This meant a 29-pound breakaway insert composed of 18 individual parts was required. The insert then separated into 3 pieces to release from the part after forming. "The breakaway alone was more intricate and difficult than many of the molds we’ve made" stated Fernando Velasco Freetech’s Vice President of Engineering. If that wasn’t enough, all the edges on the open side of the cover had a full radius molded in as it was part of the work envelope and couldn’t have any sharp surfaces. An additional breakaway section was required for the rear vent that was molded into the cover.

Machined trimming for all the parts was done on 5-axis CNC routing equipment using the 3-D CAD files to make holding fixtures. This insured that even though there isn’t a single square or perpendicular surface on the exterior of any of the parts they would still interface properly with sheet metal and weldments that were. All the parts required 3D-machined fixturing to hold them in the proper plane in space. These were needed to precisely machine the required sockets for holding the Ball Studs that would correctly position the covers when they were attached to the frame and casting. This assured the clean fits and match ups a product of this magnitude requires.

Needless to say this program required extremely close cooperation between, Intuitive Surgical, Lunar Design, and Freetech Plastics. But the Massive number of design and manufacturing awards this system has achieved show that the effort did not go unnoticed.