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Have read in the boating magss about skyhook but no nothing else; is it available for outboard boats? who is the real vendor vs add-ons? Sounds awesome but is this something the average boater can buy and use?
its software that links your GPS, engines and controls. basically lets you "hover" in place without you having to do anything but fish... read about it relative to some of the new drives for inboards, eliminates the need for anchoring to stay above a reef or wreck but I can't find anything detailed on it or if outboards are planned
Skyhook is an option for the Mercruiser/Cummins Zeus pod-drives and Axius stern drives as far as I know...
Both systems require each drive to be individually articulating so that the prop thrust from each engine can be forward/reverse, and any direction. This is to aid primarily in docking, which along with slow speed operation, is done with a joystick.
Does not apply to outboards; and last I heard Skyhook had been taken off the market because of "bugs". Anyone intimate with what's going on at Mercury these days please comment further...
Skyhook and Docking Mode for all outboards and I/Os
My company (Tecnautic.com) makes autopilots with Hover Mode, suitable for all outboards and Stern Drives.
The propulsion system must be able to push the vessel sideways while maintaining heading. That is achieved by automatically steering the drives to individual angles, when in Docking Mode or Hover Mode. The available sideways thrust is a function of boat geometry. A spacing between the drives of a quarter boat length can convert the available forward thrust into 50% sideways thrust of one engine - without pushing the boat forward or aft, and while automatically maintaining heading on the gyro at the same time. That is really a lot of force, compared to conventional thrusters.
Only on closely spaced outboards, less side thrust may be available. Spacing between the outboards must permit individual steering without interference. Making the Drives independent from each other is not a big thing in most cases.
As xzp's post implies, supposedly the outboard version should work very well on twin engine cats, where there is a great deal of motor separation. On conventional twins, probably the motors might need to be at least a little further apart than they usually are. And of course, the conventional steering tiebar between engines has to go, and the steering needs to be modified accordingly.
Note xzp's figure, one-fourth of boat length on a 26, say, would translate into motor separation of roughly six-seven feet. However, that is NOT required. It is just that you will lose some of the available side force with closer spacing.
I think this will be REAL big pretty soon, but we shall see. I had also thought Mercury was supposed to be working on this (for outboards) as well, but maybe that is the same (Tecnautic) system.
My company (Tecnautic.com) makes autopilots with Hover Mode, suitable for all outboards and Stern Drives.
The propulsion system must be able to push the vessel sideways while maintaining heading. That is achieved by automatically steering the drives to individual angles, when in Docking Mode
xvp
How does your system handle the fact that with outboards, the amount of rotation available is generally quite a bit less than is available with a pod drive? In other words, does forward to reverse shifting need to be done, on one engine or another, from time to time, and if so, how is that handled, or can the necessary angles of force be achieved with the motors in forward at all times?
The steering angle that lets the boat accelerate straight on one engine (from stand still) is the basic spread angle in Docking Mode. Swift Heading changes are made through the electric steering wheel by small changes on top of the basic Spread angle. The reversing Drive makes mirrored deflections. For a certain wheel deflection, the boat will always turn to the same side and at the same rate of turn, no matter if moving forward or astern or halted.
There will always be one engine in forward and one in reverse gear. In Joystick-Mode and Hover-Mode the autopilot is taking care of the throttles.
In Docking-Mode with manual throttles, the helmsman has to set opposite throttles. To reverse the sideways motion, he reverses the throttles, making sure not to remain in neutral. Note that the boat cannot be turned with the throttles. No matter what you do, it will keep the heading (and move forward/aft or to port/starboard)! Only the Fly-By-Wire Steering Wheel lets you change the heading.
Thanks, that makes it a lot clearer. Sounds really slick. Any idea (well, I'm sure you have an idea, but can you share the info) of what this system is going to run, approximate price, and when it may be available? Will most any dealer or up-to-snuff DIY'er be able to install it, or is it going to require your guys to install? Seems like the install wouldn't be real difficult at all, except maybe for the steering. More I think about that, it's not just the tiebar, but you are going to have to have, in effect, two totally separate steering systems.
The one engine ahead, one in reverse, at all times answered my main question. I thought there would have to be some reverse in there somewhere.
Thanks, that makes it a lot clearer. Sounds really slick. Any idea (well, I'm sure you have an idea, but can you share the info) of what this system is going to run, approximate price, and when it may be available? Will most any dealer or up-to-snuff DIY'er be able to install it, or is it going to require your guys to install? Seems like the install wouldn't be real difficult at all, except maybe for the steering. More I think about that, it's not just the tiebar, but you are going to have to have, in effect, two totally separate steering systems.
The one engine ahead, one in reverse, at all times answered my main question. I thought there would have to be some reverse in there somewhere.
Good luck with this.
The Fly-By-Wire system is already available for years (www.tecnautic.com). There are only a few parts to be added to the standard autopilot, to let you move the boat sideways. Basically it's a second Drivebox and a second autopilot pump and steering ram.
On installations without Tecnautic electric throttles, a Microswitch at the shift actuator (or shift cable) has to sense when an engine is in reverse. The software that takes care of individual steering angles is standard in the Autopilot Drivebox.
Skyhook for outboards?
