Going to fab! (Trident Kickstarter Update #15)

Original post : September 15, 2016

Hello Everyone,

First, the good news: we've gotten the thumbs up from our mold manufacturer that our design is ready for tooling! Getting to this major milestone took a little more time than we had originally planned. Here’s why: over the past ten weeks, we've organized several external design reviews with industry experts to get feedback on our design. This extra step ensures that the Trident we ship will be of the highest quality and reliability. We’ve had to make some tough calls on whether or not to take the extra time to make revisions based on the feedback we’ve received during the review process. In the end, we chose to be thorough and to pay attention to every detail. At this point, we think these changes will delay our shipping schedule by about six weeks (so early Kickstarter backers would get their Tridents around January, and pre-order customers would receive theirs around March/April). We’re still waiting to get a precise updated lead-time estimate from our tooling manufacturer so we’ll have more information later, but we wanted to get the initial word out as soon as possible.

To get more specific, here are some of the changes we've made to the design during our design for manufacturing DFM iterations phase:

  1. Redesigned the sealing surfaces to allow thicker o-ring material between the top and bottom shell plates which will help ensure a reliable seal.

  2. Increased and relocated fastener positions throughout the shell to counteract typical warp and dimensional variation expected from the molding process.

  3. Added a fastening feature to the tail section to counteract warp.

  4. Increased bonding surface area for pass-throughs to ensure a more reliable seal.

  5. Added subtle filleting in several regions to reduce stress concentrations and improve moldflow during the molding process.

  6. Made adjustments to material selection to optimize weight and balance for flight performance.

  7. Redesigned the internal ballast weight to assure consistency across each assembly as well as help with thermal management.

  8. Changed the motor mounting design to allow for better alignment and consistent attachment.

  9. Added waterproof connectors to motors to improve serviceability.

  10. Changed overmolded bumper and side panel design to improve robustness and accommodate for redesigned sealing surface.

  11. Added additional groove features below each bumper to prevent it from bending outward when the ROV is held from the side.

  12. Modified LED cavities to improve resilience against frontal impact.

  13. Added plastic collet design around camera lens to keep it centered in the window and improve strength against frontal impact.

  14. General improvements to motor cover design.

  15. Modified fastening and supports for internal PCBs.

  16. Added mating features on reciprocal screw bosses to strengthen against shear movement between top and bottom shell pieces.

We've also upgraded the material for the camera window from glass to sapphire in order to protect the vehicle from scratches and cracks. Sapphire is the second hardest mineral on earth (next to diamond) and is extremely scratch resistant. You can see us do a comparison test here. Although sapphire is very expensive, we felt it was important to make Trident as durable as possible - particularly when it comes to getting great video in rough field conditions.

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Sapphire window (left) vs glass window (right) after abrasion with steel screwdriver

Every change we’ve made seems minor when considered individually, but they add up. For comparison, here’s a photo of the evolution Trident has had since we launched Kickstarter:

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(Left) Prototype used for initial filming of Kickstarter video, (middle) prototype used for early engineering tests, (right) current (Rev-8) prototype. Off-white color of Rev-8 prototype is from urethane casting. Production models will be pure white.

As much as we take pride in optimization, we want to respect the timeline that we’ve laid out. We've been fortunate that no major issues have arisen in our development process so far, but the phase we are entering now (ordering and expecting parts from suppliers, getting first articles from manufacturers, etc.) is one of the thorniest.

Our methodology for this phase will be to continue to communicate as much as possible. If we find out about something that will cause a delay, we will let you know right away. However, we will not allow things to get sloppy by rushing them.

Trident is more than just a product to us. Most of our team has spent many years working with ROVs and this project represents the culmination of everything we’ve learned. We are putting our hearts into this project and we hope the outcome reflects that commitment.

As always, we would like to thank you for your support in making this project possible. Let us know if you have any questions.

Eric