Design philosophy: Do away with knob interfaces at all cost yet maintain the same dexterity, degrees of freedom, strength and aesthetic appeal as with as design using knobs.

Materials: Wood, recycled and non recycled rubber, plastics possibly recycled, aluminum. Ideally, the materials would be used as shown with the tubing and mechanicals in aluminum however I designed it robust enough so that every part (except rubber components and springs) could possibly be 3D printed. Some rough estimates for 3D printed parts can be found @,,

Budget spectrum: midrange. Although seemingly complex, most of the mechanical components can be CNC’d from aluminum in mass quantity, 3D printed or injection molded for reasonable cost.

So in this design, although seemingly more complex in construction than previous concepts, the main idea was to do away with manual adjusted knobs of any kind and provide the user with the benefit of adjustability in its’ bare form. With the robot, the user doesn’t have to be aware that he is making a complex set of adjustments to his/her rod just to get the desired angle, they simply need to point the rod in the direction they want it and it stays there for good, locked in position.

For this design, I was inspired by the way motor cycle transmission gears work to lock into each other, more specifically, the kick start mechanism. So I developed a version that could be used in this application. Two interlocking gears mesh until pulled apart, simply, a spring is used to supply the return force to re-mesh the notch faced gears. My design allows for 18 different positions of adjustability around 360 degree, with only .13” of distance required to unlock the notched faces to allow for rotation. The notched plates allow for lateral pivot movement (rotation on horizontal plane, **well slightly tilted but might rework that) and another to allow for pivot of the holster up and down (rotation on vertical plane). All the user needs to do is to push down .13” to disengage the notched plates and simply rotate into position, the heavy duty return spring reengages the notch plates and everything is held in place tightly, no slipping, no walking, where you place it is where it stays, all without the need to adjust any knobs or having to worry about them loosening. The same procedure is used to pivot the rod up and down on the verticle, simply hold the base of the holder and pull out .13”, pivot and let it find it’s position to snap back into place. All set.

With regards to the boat clamping method, again the focus was for simplicity. Two padded claws are simply rotated about 27 degrees and the pads slide under the bottom boat ledge to secure everything snuggly. The claws are attached by 2 screws and custom made slider plates, the screws are tightened snuggly just enough so the claws can be rotated into the open and closed position. The only issue that could arise is that the rotational forces of the rod and rod holder slowly work to reopen the clamp, prototype testing would need to be done but if this were the case, simply added a small knob to additionally tighten the claws should suffice.

Please check out the attached .pdf with the complete list of parts required and the included BOM.excel, it’s a work in progress but I have received estimates for injection molding some parts. Trapper, don’t let the complexity intimidate you, it’s actually quite a simple design. The idea would be to have most of the mechanicals CNC’d in aluminum, the plastics and rubber, injected molded and the wood parts CNC’d. My extremely rough estimate would put the unit cost at possibly 50-100$ with possibly, but hopefully under 50$US per unit with 50,000-80,000$ in upfront tooling costs, but the BOM needs to be fully completed, just a super ball park estimate >>will update BOM as I estimates come in.

Download Rod Holder concept4: The Robot 3D Model Files

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