By Michael Landis, manager of Product Development at PADTProduct development isn’t simply about creating something new or building on the success of an existing product. It’s also about improving the design process itself: Integrating the best of today’s tools to build better products faster and cheaper. For Globalstar, makers of the SPOT personal global positioning system (GPS) communication device, that meant tapping the expertise in CAD design and 3D printing at Phoenix Analysis & Design Technologies (PADT) for its next-generation product. Putting the digital material capabilities of a Stratasys Connex3 printer to work made the difference.
Success in Remote Places
Globalstar’s SPOT GPS satellite messenger is a personal communication device that uses 100% satellite technology and works virtually anywhere in the world, even where cellphones do not. In non-emergency situations, SPOT allows you to check-in with family and friends to let them know you’re ok when you’re out of cell phone range. You can send a pre-programmed text message with GPS coordinates or an email with a link to Google Maps to your contacts with your location. You can even allow friends and family to follow your progress online in near real-time and save waypoints so you can review your entire route at a later date.
If you need help in non-life-threatening situations, the Help/SPOT Assist feature will alert your personal contacts or can be used to contact professional services on land. And perhaps most importantly, SPOT provides a critical, life-saving line of emergency assistance. The push of a button will trigger the GEOS International Emergency Response Coordination Center to provide your GPS coordinates and information to local response teams. SPOT has initiated 4,000 rescues since it was first launched in 2007, saving untold numbers of lives.
Innovating the Third Generation
Globalstar engaged PADT to assist in the design of its third-generation SPOT device. Globalstar’s major objective was to simplify and make the manufacturing/assembly process more repeatable, while maintaining the existing environmental specs, yet reducing the size and cost of the device without adversely affecting the design’s aesthetics.
The product line had certain hardware features that needed improvement. Earlier SPOT generations were prone to inadvertent activation of the “SOS” button. Globalstar also sought a design that harkened back to its roots with the profile, enhanced ergonomics and improved tactile response of a modern high-end device.
Because SPOT is designed to work virtually everywhere in the world, the SPOT3 was also required to operate under demanding outdoor conditions, across a wide temperature range (-40°C to 85°C) and altitude range (-100 meters to +6500 meters). It had to be waterproof, durable, droppable, marine oriented and RoHS compliant.
Using good engineering practices and general industrial design methodologies, PADT worked with Globalstar’s marketing group and its industrial designer team upfront to closely define the product requirements. In place of an artistic sketch, photo-realistic renderings created in the CAD program SOLIDWORKS were produced to evaluate the visual appeal of multiple designs. Collaborative design reviews were held at key decision points to achieve enhanced ergonomics and functionality while maintaining the established brand identify and the rugged, durable appearance that the SPOT product line was known for.
Using various digital materials listed in Fig. 2, PADT then exported the leading design concepts for printing on a Stratasys Connex 3D printer and sent them to its model shop to produce three different concept prototypes with the correct colors and textures. This process was completed in about three weeks, a tremendous time savings as compared to injection molded prototyping in short-run production volumes, which typically takes a minimum of six weeks.
These prototypes provided the Globalstar team with a hands-on evaluation of the look and feel and actual size and shape of the options such as chiseled rather than rounded features.
|Spot3 prototype part||Digital material|
|Back Housing||Verowhite / DM9860|
|Button Cover||Verowhite / DM9860|
|Front Housing||Verowhite / DM9860|
|USB Cover||Verowhite / DM9860|
Perfecting the SOS Button
3D printing also helped PADT design the perfect “SOS” button guard for the SPOT3 that was secure, yet not too tricky to disengage in an emergency situation.
Several concepts for the button guard were first defined. Once an option was selected by the engineering team, just the button cover was 3D printed to test how well it worked. This process was iterated for each component in the button.
At the same time PADT was designing the plastics, the Globalstar team was completing the layout of the printed circuit board (PCB). It was important for the Globalstar team to understand the layout of the key features and properly place them on the board. PADT was able to actually 3D print the parts and create a “dummy” board so that a fit check could be carried out. The result was a realistic plastic prototype as opposed to an industrial design in a solid block. It was very close to the actual end product consistent with high volume manufacturing methods, materials and processes, smoothing the path for collaboration with offshore injection molders. Once the electronics were completed, the Globalstar team used the 3D-printed parts to produce functional prototypes for field testing.
Without the luxury of having 3D-printed parts, design issues might not have been found until each part was actually in mold production. Being able to 3D print the parts, do a fit check evaluation, troubleshoot it, and in a day make a reprint of the design that was checked again, provided time and cost savings and led to better quality results. The PADT team was able to test each small part feature in the SPOT3 to near perfect accuracy, and then later make final needed adjustments to the mold during the actual manufacturing process.
Bumps in the Product Development Road
Issues are a realistic aspect of product development, so it’s all about being prepared to handle them. PADT coordinated directly with Globalstar’s contract manufacturer to work out any design for manufacture (DFM) issues and resolved some variance problems that occurred as the design was transitioned from initial prototypes into mass production.
There were several cases of material and molding process issues during evaluation of the first batches coming off of the mold. This involved double shot over molding adhesion problems as well as stress fractures and sealing surface deformation that impacted cosmetic and environmental performance. PADT was able to modify the design and the material specification to get the product into compliance.
Globalstar also ended up needing a secondary daughterboard PCB for getting its USB connector out to the perimeter of the plastics without adversely affecting the design size/aesthetics. PADT worked closely with Globalstar’s PCB layout team to ensure that there were no misalignment problems by being able to convert back and forth between the two CAD systems.
The impact that 3D printing had on the rapid prototyping process used to design the third generation SPOT was significant. Ideas were developed faster and parts were created at a fraction of the expense of traditional machining. Printing a production-ready prototype gave the Globalstar team confidence before they made the investment in expensive molding tooling. Finally, clearer communication and feedback from a physical prototype is something you just can’t get from a picture or virtual prototype on a computer screen. If you want to ensure the ergonomics and fit of a product are just right, you must actually hold it, use it and test it.