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#11
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Jet Boat Autopilot
On Sun, 30 Nov 2003 00:44:53 +0100, Michael Ohlhorst wrote:
my promblems setting up an Autopilot to my 10foot tube tender was the compass. the ractions of the compass where to worse to use it. The semiregide inflatable with 40HP Johnsen is rigged with a hydraulik steering system and the hydraulik pump works fine. when the boot hurts in the sea my small compass ist circeling and the fluxgate of the autopilot do not deliver usefull data sets. The Autopilot ill tried was a small DANAHELM unit the first fluxgate has aircoils and the second was oil filled. The idear adapting NMEA Data from a GPS Handheld could work but the time to patch the software of the autopilot to get it work would be to long for me. Michael from Germany Hi Michael, Ok, so then you're saying that the data delivered by fluxgate compasses was the problem. I can understand that, particularly as a small boat always has far more pitch and roll than a larger craft. (My boat is small as well) In fact, I recall something said by the owner of the boat I was aboard saying something like autopilot wasn't that useful in rough weather, but that might well have been because you tend to need to head into it and it shifts, while an autopilot might want to take you in a different direction. I am pretty sure that modern autopilots can and do accept NMEA data. That must be the case as some advertise that they work with GPS to follow a plotted course, so it would appear as if there wouldn't need to be any modification. I have the skills necessary to modify software (I'm a software engineer by trade) but I doubt companies would release the source. Thanks for sharing your experiences. -- Larry email is rapp at lmr dot com |
#12
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Jet Boat Autopilot
Hi Larry,
Ok, so then you're saying that the data delivered by fluxgate compasses was the problem. I can understand that, particularly as a small boat always has far more pitch and roll than a larger craft. (My boat is small as well) In fact, I recall something said by the owner of the boat I was aboard saying something like autopilot wasn't that useful in rough weather, but that might well have been because you tend to need to head into it and it shifts, while an autopilot might want to take you in a different direction. I would not say that the small tender is doing more pitch and roll than my bigship. The reason for the worse funktions are the hard knoking when it falls back to the water its nearly flying most of the time 40HP at 300Kilo gramms. I am pretty sure that modern autopilots can and do accept NMEA data. That must be the case as some advertise that they work with GPS to follow a plotted course, so it would appear as if there wouldn't need to be any modification. The first promlem could be that the GPS data is comming out once a second wile the compass Data are 5 to 20 times a second appears. All autopilots i have seen are using the compass for the direction and do the correction with the cross track information only. I have the skills necessary to modify software (I'm a software engineer by trade) but I doubt companies would release the source. For my old DANAHELM it was the reason to remove it from the ship and replace it with an robertson AP3000 Danahelm is gone out of the business and i had not the time to repair the compass for a while. Later i saw that only one TTL in the output has blown. The Danahelm uses an 80535 as the main prozessor so it could not be too difficult to disassemble the operating software. the robertson uses also an 8051 derivat. Michael |
#13
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Jet Boat Autopilot
Hi Larry,
I recall from years ago that handling large craft was very much the same thing: you applied rudder and the reaction was delayed. Stopping was similar - you approached slowly and with caution and reversed engines well before you wanted to stop. All of this is what I generically call "damping" - anticipation of the effect and a delayed reaction to change. Now my experience with autopilots is practically nil - the only time I used one was very brief and basically it just kept the boat on course. I had hoped that when you set up an autopilot, that you could trim the amount of steerage. Are you saying that you can't? As i am going most often alone with my Boat i have to use the autopilot for a lot of times when i am busy. The worst situation was a trip at the german north sea between Cuxhafen at the Elbe and Helgoland the distance is around 70 miles open water. The weather has turned from bad to impossible and as my flybridge was not ready to use i had to steer form inside. The lithouse of Helgoland was in sight but i was not able to steer a usefull course. The waves are so strong that my dutch 52feet Motorboot was doing 90 degree course changes within 5 seconds. The only way for me was using my robertson AP3000 sitting on the sofa and hoping the best -which lasts 5 hours as the boat is doing around 8 knots in good conditions. The trimming of an autopilot is the most horrible thing to do. When it is funktioning in calm conditions it is not working in rough sea and when its working there your boat is moving like a drunken sailor at a mirror sea. Michael |
#14
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Jet Boat Autopilot
Like Michael said Larry,........... Every boat & every sea (following, head,
etc) has it's own particular set of behavioral problems or idiosynchrosies. I think as long as you don't expect it to be a really sucessful setup, then you won't be disappointed. I had a chat today with a pro fisherman & he said that if you set it too "tight", all your equipment in the steering department would be "overworked" trying to keep you on course that it wouldn't last long. Much of his work is in seas with a diagonal swell on his way out & back from the grounds. His auto-pilot is set with a wide path so that the boats natural veering behaviour on the up side is allowed to "happen" without correcting so that the natural opposite veering in the other direction on the down side is back to within the course allowed. Hope I'm making sense. If the pilot has to "fight" it one way, it then has to also "fight" it the other. That is with a boat that has a decent skeg & a big rudder. Probably similar to a yacht with a decent keel. Imagine a yacht without a keel? All in all, with a jet, don't expect too much. "Michael Ohlhorst" wrote in message ... Hi Larry, I recall from years ago that handling large craft was very much the same thing: you applied rudder and the reaction was delayed. Stopping was similar - you approached slowly and with caution and reversed engines well before you wanted to stop. All of this is what I generically call "damping" - anticipation of the effect and a delayed reaction to change. Now my experience with autopilots is practically nil - the only time I used one was very brief and basically it just kept the boat on course. I had hoped that when you set up an autopilot, that you could trim the amount of steerage. Are you saying that you can't? As i am going most often alone with my Boat i have to use the autopilot for a lot of times when i am busy. The worst situation was a trip at the german north sea between Cuxhafen at the Elbe and Helgoland the distance is around 70 miles open water. The weather has turned from bad to impossible and as my flybridge was not ready to use i had to steer form inside. The lithouse of Helgoland was in sight but i was not able to steer a usefull course. The waves are so strong that my dutch 52feet Motorboot was doing 90 degree course changes within 5 seconds. The only way for me was using my robertson AP3000 sitting on the sofa and hoping the best -which lasts 5 hours as the boat is doing around 8 knots in good conditions. The trimming of an autopilot is the most horrible thing to do. When it is funktioning in calm conditions it is not working in rough sea and when its working there your boat is moving like a drunken sailor at a mirror sea. Michael |
#15
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Jet Boat Autopilot
On Mon, 1 Dec 2003 17:26:34 +1030, BruceM wrote:
Like Michael said Larry,........... Every boat & every sea (following, head, etc) has it's own particular set of behavioral problems or idiosynchrosies. I think as long as you don't expect it to be a really sucessful setup, then you won't be disappointed. I had a chat today with a pro fisherman & he said that if you set it too "tight", all your equipment in the steering department would be "overworked" trying to keep you on course that it wouldn't last long. Much of his work is in seas with a diagonal swell on his way out & back from the grounds. His auto-pilot is set with a wide path so that the boats natural veering behaviour on the up side is allowed to "happen" without correcting so that the natural opposite veering in the other direction on the down side is back to within the course allowed. Hope I'm making sense. If the pilot has to "fight" it one way, it then has to also "fight" it the other. That is with a boat that has a decent skeg & a big rudder. Probably similar to a yacht with a decent keel. Imagine a yacht without a keel? All in all, with a jet, don't expect too much. "Michael Ohlhorst" wrote in message ... Hi Larry, I recall from years ago that handling large craft was very much the same thing: you applied rudder and the reaction was delayed. Stopping was similar - you approached slowly and with caution and reversed engines well before you wanted to stop. All of this is what I generically call "damping" - anticipation of the effect and a delayed reaction to change. Now my experience with autopilots is practically nil - the only time I used one was very brief and basically it just kept the boat on course. I had hoped that when you set up an autopilot, that you could trim the amount of steerage. Are you saying that you can't? As i am going most often alone with my Boat i have to use the autopilot for a lot of times when i am busy. The worst situation was a trip at the german north sea between Cuxhafen at the Elbe and Helgoland the distance is around 70 miles open water. The weather has turned from bad to impossible and as my flybridge was not ready to use i had to steer form inside. The lithouse of Helgoland was in sight but i was not able to steer a usefull course. The waves are so strong that my dutch 52feet Motorboot was doing 90 degree course changes within 5 seconds. The only way for me was using my robertson AP3000 sitting on the sofa and hoping the best -which lasts 5 hours as the boat is doing around 8 knots in good conditions. The trimming of an autopilot is the most horrible thing to do. When it is funktioning in calm conditions it is not working in rough sea and when its working there your boat is moving like a drunken sailor at a mirror sea. Michael Thanks to all, I've done a bit more research in addition to what I've read here and pretty much decided to scrap the idea. Bombardier is just about useless - virtually no technical help at all. When I asked them about adding an autopilot, they said they would not help and would pull the warranty if I did. I already had a brand new engine blow, and the deaIer had to fight with them to replace the engine with a new one. I think I'll no doubt sell it next season while the new engine is still working. First and last experience with Bombardier. I added trim tabs, and they have helped it a bit, but after visiting the Hinckley site, I am remembering what real boats are like.... For now, I guess I'll just use my knee to hold the wheel while I eat my sandwich! I'll start a new thread about the new boat in a different boating group. -- Larry email is rapp at lmr dot com |
#16
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Jet Boat Autopilot
I jumped in late here but if your goal is to let go of the wheel and have the
boat continue to go straight I would suggest going with a "no-feedback" steering system. If you have Teleflex steering components already, it can be retrofitted pretty cheap. I have it on my boat and it's great. It's a "poor man's" hydraulic steering and ideal for lower HP ranges. I'm not too familiar with jets but I would imagine that hydraulic steering would be an option anyway. In the interest of safety, you wouldn't want to let go of the wheel at any high speeds or in rough conditions. For me, it's great because I can make a quick run to the cooler or the washdown while idling back on the way to the slip on the ICW. The other bonus is that at high speeds the wheel doesn't pull to one side and when you accelerate quickly you don't have that engine torque on the wheel. Dan Larry wrote: Thanks to all, I've done a bit more research in addition to what I've read here and pretty much decided to scrap the idea. Bombardier is just about useless - virtually no technical help at all. When I asked them about adding an autopilot, they said they would not help and would pull the warranty if I did. I already had a brand new engine blow, and the deaIer had to fight with them to replace the engine with a new one. I think I'll no doubt sell it next season while the new engine is still working. First and last experience with Bombardier. I added trim tabs, and they have helped it a bit, but after visiting the Hinckley site, I am remembering what real boats are like.... For now, I guess I'll just use my knee to hold the wheel while I eat my sandwich! I'll start a new thread about the new boat in a different boating group. |
#17
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Jet Boat Autopilot
On Thu, 27 Nov 2003 17:25:21 GMT, Larry wrote:
I have a Bombardier Utopia 185 jet boat, powered by a Merc 100hp DFI jet. That is an 18.5 ft bowrider runabout. I would like to add an autopilot to it. Anyone have any recommendations? Has anyone added an autopilot to a jet boat and have any suggestions? Thanks The more financially endowed salmon fishermen around here have been installing TR-1 autopilots on their kicker motors. A friend of mine has one on his boat, it's very impressive... The unit can be used for the main engine as well as the kicker, with the approprate actuators. Check http://www.nautamatic.com/ Dan |
#18
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Jet Boat Autopilot
On Wed, 03 Dec 2003 01:42:28 GMT, Dan Krueger wrote:
I jumped in late here but if your goal is to let go of the wheel and have the boat continue to go straight I would suggest going with a "no-feedback" steering system. If you have Teleflex steering components already, it can be retrofitted pretty cheap. I have it on my boat and it's great. It's a "poor man's" hydraulic steering and ideal for lower HP ranges. I'm not too familiar with jets but I would imagine that hydraulic steering would be an option anyway. In the interest of safety, you wouldn't want to let go of the wheel at any high speeds or in rough conditions. For me, it's great because I can make a quick run to the cooler or the washdown while idling back on the way to the slip on the ICW. The other bonus is that at high speeds the wheel doesn't pull to one side and when you accelerate quickly you don't have that engine torque on the wheel. Dan I don't know which steering components are installed and Bombardier (the manufacturer) won't tell me. I believe they use a cable system of some kind. I'm kind of fed up with them and will probably sell the boat this summer and get a real boat. (sarcasm) . I did a quick Google for Teleflex, though and got a bunch of information. Thanks for the tip. -- Larry email is rapp at lmr dot com |
#19
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Jet Boat Autopilot
On Wed, 03 Dec 2003 02:43:56 GMT, Cantide wrote:
On Thu, 27 Nov 2003 17:25:21 GMT, Larry wrote: I have a Bombardier Utopia 185 jet boat, powered by a Merc 100hp DFI jet. That is an 18.5 ft bowrider runabout. I would like to add an autopilot to it. Anyone have any recommendations? Has anyone added an autopilot to a jet boat and have any suggestions? Thanks The more financially endowed salmon fishermen around here have been installing TR-1 autopilots on their kicker motors. A friend of mine has one on his boat, it's very impressive... The unit can be used for the main engine as well as the kicker, with the approprate actuators. Check http://www.nautamatic.com/ Dan Thanks, Dan, I had looked at them. They're really pricey and I can't get an answer about retrofit. -- Larry email is rapp at lmr dot com |
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