Expedition Navigation Software 
1 of 1- rbhun
- Expert
Offline - Registered: 7/05/2019
- Posts: 103
is heel/
Hi
when I started using KND racereplay it turned out my GPS is sh*t. Not suprisingly, as I have old raymarine instruments. For a quick solution before a race, I bought a 30$ gps puck, which improved position and COG/SOG. I also tried using GPS2IP on the control ipad to send its sensor data to Exp.
I am now thinking about buying a more expensive compass. I understand the gain in position precision, and 10Hz vs 1Hz. I am not sure how other sensors and data would improve our daily life 
especially as we are a hobby crew with lot of things to improve and spend money.
I understand heel in itself, and I can see it has a calculation factor in leeway. Does heel and other info from gyroscopes play a part in wind calibration, or anything else? I suppose it does in B&G Hercules, when it does 3D calibration, but does Exp has similar things? I am not planning on buying a B&G processor soon, so I'd do most calibration in Exp.
Also, does altitude or barometric pressure plays any role here?
thank you
- DuncanR
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- From: Up and down East Coast Aus
- Registered: 9/16/2015
- Posts: 465
Re: is heel/
Rb, you are on the right track. OF COURSE it is good to have a heel sensor - apart from anything else, it allows for speedo calibration at heel and an understanding of your ship's performance at heel, to me both more important than a theoretical calculation of leeway.
You talk about buying a new compass, I assume because of the refresh rates. They aren't an expensive investment in the scheme of things if you go from 10Hz data to 1 Hz data..
Down here off the east coast of Australia, barometer is good, but with the East Coast Current (AKA Finding Nemo movie), a seawater temperature sensor is critical. Horses for courses!
Hope this helps.
- Nick
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- Registered: 9/16/2015
- Posts: 2,740
Re: is heel/
The heel/roll affects the awa measurement.
So if you have a heel sensor, Exp, B&G etc correct for it in the wind calculations.
- rbhun
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- Registered: 7/05/2019
- Posts: 103
Re: is heel/
Great, thank you guys! I have talked with the developer of gps2ip, and he is incorporating heel and roll. I’ll probably try that before I comment to buying new stuff.
Do you need to enter the length of the mast (distance between the anemometer and turning point) to know how the move of the mast is affecting it?
Just to clarify the terminology, heel is side to side, roll is front to back (like on waves) but what’s heave?
- •
Thread Starter- sparky
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- From: Cambridge UK
- Registered: 4/27/2018
- Posts: 224
Re: is heel/
Heave is up and down...
- Campbell_Field
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- From: UK
- Registered: 9/16/2015
- Posts: 208
Re: is heel/
rbhun wrote:
Great, thank you guys! I have talked with the developer of gps2ip, and he is incorporating heel and roll. I’ll probably try that before I comment to buying new stuff.
Do you need to enter the length of the mast (distance between the anemometer and turning point) to know how the move of the mast is affecting it?
Just to clarify the terminology, heel is side to side, roll is front to back (like on waves) but what’s heave?
Sorry, but roll is not 'front to back'
By definition Heel/Trim/Heading are the static angle of a yacht around the X/Y/Z axes (repesctively) and Roll/Pitch/Yaw is the dynamic component sometimes referred to as Roll/Pitch/Yaw Rate, or in the case of Yaw Rate - ROT (Rate Of Turn).
Surge/Sway/Heave are dynamic in the plane of the X/Y/Z axes - in the case of Surge, the static component is Boatspeed.
All without consdering Leeway (i.e. X is Heading, not Course, therefore Surge is in the X axis, there would be an element of Sway and Heave due to leeway and heel).
Please feel free to fact check me!
Last edited by Campbell_Field (9/03/2020 1:00 am)
:::Campbell Field::::::www.fieldyachting.com:::
- Stedfeldt
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- Registered: 2/02/2020
- Posts: 5
Re: is heel/
Hope it is OK to piggyback on this topic. If using Expedition to calculate AWA, TWA and TWD, corrected for Roll and Pitch, what would be a reasonable update frequency of Roll and Pitch? In my case, I have an NMEA 2000 network directly connected to PC/Expedition via Actisense NGT. The Wind sensor provide AWA_raw in 20 Hz, BSP in 4 Hz, and Heading (T) in 10 Hz.