Considerations
- Compact small lightweight
- Robust
- Quick to install
- Easy to adjust
- Cannot unintentionally move while body worn
Initial Research
Initial mount need was discovered during Session camera mount research. This investigation revealed that our current side helmet mount and Sessions camera do not create a compelling story in terms of a much smaller camera. Currently 3 axis of adjustment requires 2 extension arms and 3 thumb screws. All of which have to be adjusted independently, have to be reassembled differently, depending on the side of the helmet used, and look bulky.
Initial prototype:
The first prototype was built using a Joby micro tripod ball joint and a modified QR low and tripod mount. This didn’t have the desired torque but allowed us to prove out the range and user experience.
This prototype was used to test range of motion and proof of concept. The prototype motion range was 28-30 degrees (14-15 degrees off center)
Because of the mounts adjustment ability precise alignment of the QR base is no longer important. This allows for quicker installation and more mounting options. Installation and camera aiming takes all of 3 seconds. Reversing the camera from left to right side is simple and requires no disassembly.
Investigation
First we determined a ball park torque required for our ball joint. An accelerometer was attached to a few people doing activities. The max recording of G’s was approximately 5. As a margin of safety we doubled this amount and assumed our mount would need to not move from a 10 G shock.
The illustration shown gave us the initial torque requirement of 7” lbs I began to examine small joints at this level. Unfortunately plastic ball joints, that can provide enough friction, are large in order to work. They require a lot of surface area to get the friction force required. This concept required a large amount of friction in profile small enough to fit in a QR profile. Therefore metal ball joints were explored.
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I knew of and contacted a few companies that specialized in making small friction joints. Both companies make what is referred to as self-aligning bushings. These bushing/ bearings are typically used to accommodate assembly or out of tolerance parts. They allow the shaft bushing to pivot slightly. These bushing typically only move a few degrees. We required many more.
Final Concept
Size, reliability, and material, were the major factors in our decision to the Spyraflo vendor for our concept. We received drawings of their final concept and incorporated this into our 3-d model. Precision parts in the USA would eventually be shipped to China for final assembly.
The sweet spot
This concept relies on friction of the ball being easy enough for the user to move, but hard enough to not move while being used. To find this “sweet spot” a made a torque tester to get user feedback on what felt like an appropriate adjustment force.
Average user requested 5-6” lbs of measured torque. This gave us approximately 15” lbs of torque at the ball. I then took this setup and attached it to a vehicle to see if it could survive wind and vibration, and shock without moving. The ball joint passed these conditions. |
Although originally designed for body worn applications and low impact, were were able to dial in a torque that also allowed the mount to be used on most motorcycles and automobiles as well thereby increasing the consumer market by many times. The Swivel mount proved to be perfect solution for offsetting slightly curved body surfaces and inside the car windshield.