Dec 2010 V1.00. What Makes a Marine PC? A review of the main design features of Digital Yacht s Aqua PCs. Aqua PC.

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1 Dec 2010 V1.00 What Makes a Marine PC? A review of the main design features of Digital Yacht s Aqua PCs Aqua PC Product Overview

2 On Board the Boat. o Damp, Salty Air minimise ingress o Pitching and Rolling mounting problems o Pounding high G forces o Vibration long term stress fatigue o 12v or 24v DC supply o Noisy, fluctuating voltages 8v-32v o Limited battery capacity o Confined space for electronics o NMEA0183 and NMEA2000 interfacing o Equipment has to work reliably The Environment

3 Design.a matter of compromise o A fully marinised PC that meets the international IEC standard costs a lot of money to develop and to produce o Customers already have a clear price benchmark of what a PC would cost them from PC World, Dixons, etc. o A good compromise is to select and use commercial off the shelf components that are more fit for purpose in the marine environment o A good marine PC will be:- More suitable for fitting on a boat than a conventional PC Less than twice the price Repairable any where in the world for at least 5 years after purchase Design Decisions

4 Water and Electronics Don t Mix. o A fully waterproof IPX7 PC is expensive (x2-3) o Fully Waterproof = Fully Sealed = Thermal Problems o IPX7 realistically restricts the design to processors with a Thermal Design Power (TDP) of <5 Watts o Most vessels have a location which is dry enough for a PC o Over the last 5-6 years Digital Yacht have seen very few cases of acute water ingress o In general it is the long term chronic exposure to the damp atmosphere that ultimately causes failure o Conformal coating can extend the life of PC components, but can create problems when upgrading or repairing o Fanless operation is also beneficial, avoiding damp air continuously being blown across the mother board Cost v Waterproofing

5 Compact commercial case with rugged front panel design Ventilation holes required for cooling but filters added for models that feature a fanned processor Good Compromises

6 Pitching, Rolling.and Pounding o Although it might be OK to balance a laptop on the chart table in the marina, at sea boats experience incredible movement and G forces o PCs must be firmly secured to a horizontal/vertical bulkhead o Cables and connectors need to be firmly in place and where possible strain relieved with clamps or cable ties o Internal components and connections need to be minimised and large components supported o The continuous vibration and pounding will kill a normal desktop PC long before corrosion does o Hard disk drives and graphics cards are the most common points of failure Mounting

7 Mounting brackets to screw unit down to horizontal or vertical bulkhead All cables secured with cable ties Solid State Hard Drive Option Industrial shock mounts fitted to all conventional hard drives Good Compromises

8 The Boat s Supply. o All boat s have either a 12v or 24v DC supply o The majority of PCs are designed for mains operation even most laptops cannot be charged directly from the boat s supply o Inverters to convert DC to AC are inefficient and an extra system to go wrong o When batteries are low and the engine is started, brownouts or less than 10v are not uncommon o When the engine is running the voltage can rise to 14.5v or more and this can damage 12v PCs o Electrical noise from other equipment or the alternator can cause problems to PCs Power Requirements

9 o o o Use of the latest DC to DC power adaptors avoids use of inverters and mains voltages why convert DC to AC and then back again? Both boards are >95% efficient and have high input ranges 6v to 32v for reliable 12v or 24v operation Developed for commercial trucks, these boards are very reliable and support remote switch and very low current sleep modes Good Compromises

10 Limited Battery Power. o All sailboat owners are constantly worried about power consumption and normal PCs consume a lot of power o More Processing Power = More Electrical Power Low = Web Browsing, , Office Apps or Navigation Software (single tasking) Med = High = Super = HD Video or Blu-Ray playback Multi-tasking, super fast 2D/3D charting or heavy graphics (PBG or Weather Routing) Latest 3D Gaming Further Limitations

11 Entry Level, fanless Aqua PC with Intel Atom N270 (single core) processor consuming just 1.5A AquaMedia PC with Intel Atom 330 (dual core) processor and Nvidia ION graphics for HD video, consumes 2.5A AquaPro PC with Intel Core i3 processor with integral graphics for high performance and 3D charting, consumes 3.5A Good Compromises

12 Limited Space. o Space is always at a premium on most boats o Unless a manufacturer states their PC can be mounted in an enclosed space, assume that good air circulation is necessary to avoid over-heating o Allow room to access connections at the rear of the PC or enough spare cable to remove the PC from it s resting place without pulling cables out o Do not cover up ventilation holes in the PC case o The smallest PC may not be the best long term investment mini-itx is the smallest common motherboard form factor (from multiple manufacturers) o A remote power switch and USB socket is useful if PC is mounted in a difficult to access location Further Limitations

13 o Compact case size is not the smallest, but has room for optional add-ons; TV Card, Long Range Wifi Adaptor, AIS or NMEA2000 o Uses mini-itx motherboard smallest form factor from multiple manufacturers o Single Power and Data cable (1m) with two NMEA0183 interfaces and remote switch SODIMM RAM Module Passively cooled processor Good Compromises

14 Interfacing. o NMEA 0183 is the most common form of interface on board modern boats o It is a serial interface and will work with the RS232 Communication (COM) Serial Ports found on older PCs o It is very useful if your Marine PC has some COM ports but if not NMEA to USB interfaces are available make sure that compatible drivers exist for the version of Windows you are running o NMEA 2000 is the latest interfacing standard and is based on the CAN Bus technology found in cars o To interface with NMEA 2000 systems you will need a PC with an NMEA 2000 interface built-in or one of the USB to NMEA 2000 Gateway devices that are now available NMEA 0183 and 2000

15 o o AquaNav PC model comes complete with built-in dual channel AIS receiver and a pre-wired GPS antenna for simple and reliable interfacing AIS and GPS are powered independently from the PC and can be used with other equipment even when the PC is turned off o o A fully opto-isolated four port NMEA multiplexer is available as an option on the AquaPro PC All models have 3 or more USB ports Good Compromises

16 Reliability. o Modern PCs are much more reliable than they were five or more years ago o Aside from the Hardware Issues covered on the previous slides, three other factors significantly effect reliability; 1. Operating System recommend Windows 7 (32 bit) 2. Drivers always ensure devices are properly installed and have the latest drivers 3. Software - Avoid installing/uninstalling lots of different software and if possible avoid having an internet connection on your navigation PC o Get everything working and then don t change anything o If you are using your boat PC for navigation, use an old Laptop or cheap Netbook for surfing the internet, playing games, etc. No Problem Computing