Wednesday, December 11, 2013

Moving forward even when we want to go backward!

Visit for more details about the MOG Canal Boat.

The continuing saga of designing and building a unique solar powered motor yacht…

Among the unique properties of the MOG is the joy stick guidance system. The joy stick does double duty. It controls both direction and speed. The MOG has encountered an unusual phenomenon when shifting from fast forward into reverse (or vice versa). It seems this is ALSO an issue for others that use the equipment from our motor manufacturer and the people that make the electric motor controller. It is a problem that occupies the 'users' domain...... both companies do not feel they should solve the use problem, it is the province of the user.

SOoooooo,   If you remember the old stick shift 'on the floor' before the Hurst straight line shifters, there was a 'gate' (plate of metal) with a slot pattern for the shift lever to follow. Some were H patterns, Z, W, I and virtually all Italian cars had beautifully crafted, polished metal gates through which the shift lever was slid by some ne'er-do-well, aspiring Juan Fangio.

Stumble over a few score and ten years, zap, electro-mechanically a similar scenario. In order to make the rapid change of motor rotational direction appear as an acceptable command to the electronic motor controller, one must give the motor time to pause (mere thousandths of a second) but pause it must. Without the miniscule pause, the electronic motor controller and the logic board on the actual motor will not see the request for direction change. Instead of accelerating in the new (opposite direction) it again accelerates in the same (previous) direction. This has the unintended consequence of making unavoidable far objects appear a lot closer, faster and scaring you to death at twice warp speed. Beam me up Scotty!

So it becomes a 'user fix'. A physical gate must be designed that allows the correct amount of 'jiggle' for start up (prevents the motor propeller from being 'in gear' upon initiation of power) and also have a joystick dwell area (joystick slides sideways a bit before continuing its directed path) without creating a sloppy feeling gate. For now, this is the way it gets fixed. Once the fix is deemed to work, a board equivalent is built, tested and then made into a program that is effective in the motor logic and/or motor controller. 

Also, when the motor(s) change direction, the direction change must show over thirty feet away at the helm. The helm, where the steering and direction commands issued, is inside the front of the yacht. The motors are so quiet that the pilot has no other clue as to what is happening in speed or direction. Certainly not like a car that will feel like it is going backward or forward. So a method for sending and displaying these signals by wire or wireless is needed to confirm the pilots intended orders to the engine room.

This will take time and a number of frustrating failures, none of which is new to me on this 25 year sojourn through the la-la land of solar electric things. I have already made some simple thumbnails of the 2-1/2" diameter gates to be imposed over the port and starboard RC control joy sticks.

The yacht is being prepared to be hauled out of the water for a month for a spruce up of the bottom paint and some clean and detail topside. The MOG, called ALGEMAC II, will go back into the Cape Fear River, Wilmington, NC near the end of March 2014 for the close of sea trials. God willing the trials go well, Hillary and I will once again launch into continuing the Great Loop adventure.

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