A VOYAGE DATA RECORDER

FIELD OF THE INVENTION

The present invention relates generally to an apparatus for recording data regarding the operation of a sea borne vessel. More particularly, the invention relates to an apparatus for recording and protecting data using solid state storage means, whereby an apparatus of reduced size and weight is obtained.

BACKGROUND OF THE INVENTION

Solid state memory devices have been used in data recorders for recording essential data or information useful in determining causes of crashes or other mishaps in aircraft or other vehicles. When a crash occurs, it is essential that the recorded information on board survive the crash and subsequent events including heat, cold, flame, and fire that may afterwards ensue. In the event that the crash occurs over the ocean or other large body of water, the recorded information must be protected from the hydraulic pressure effects of deep water submersion.

It has long been noted that the investigation of maritime accidents and incidents could benefit from the recording of data and audible commands occurring aboard a ship. Indeed, many considered this an inevitable technological extension of the time-honored ship's logbook. This desire has culminated in the development of an international standard governing the performance of a Voyage Data Recorder (VDR).

In US Patent No. 6,706,966 is described a hardened voyage data recorder, which includes two subsystems: a removable non-volatile memory and a base containing electronics and firmware for communicating with data sensing systems and for accessing the memory. The memory is protected in a "boiler" and the electronics includes an Ethernet interface for connecting to shipboard data acquisition devices.

Current recorders can be divided into two groups:

1 ) Recorders original designed for aircrafts compromising expensive materials and technology in order to keep the weight down.

2) Recorders designed for ships, which traditionally have been much heavier and now also expensive due to the increase in prices for raw materials.

Thus, there is a need for a rugged voyage data recorder with limited size and weight designed for marine use, which can be produced at a relatively low cost.

SUMMARY OF THE INVENTION

According to the present invention there is provided a hardened voyage data recorder comprising: an inner capsule defining an interior cavity containing a data storage means; a thermal mass composition surrounding the inner capsule; an isolation material surrounding the thermal mass composition; electronic communication circuitry arranged on a communication circuit board; and an outer capsule surrounding the isolation material and being closed by a lid. It is preferred that the lid is arranged above and at a distance to the isolation material to thereby define a top cavity between the inside of the outer capsule lid and the isolation material, with the top cavity containing the communication circuit board.

It is within an embodiment of the invention that a mounting plate is arranged above or on top of the isolation material, and that the outer capsule lid is arranged above and at a distance to the mounting plate thereby defining the top cavity between the inside of the outer capsule lid and the mounting plate.

It is preferred that spacers are extending between the mounting plate and the inner surface of the outer capsule lid. It is also preferred that the communication circuit board is secured to the mounting plate at a distance above the mounting plate.

It is within one or more embodiments of the invention that the lid of the outer capsule has one or more ducts for electrical wiring extending from the outside of the outer capsule lid to the inside of the outer capsule lid, and that the electronic communication circuitry has electrical signal connection with the electrical wiring.

The data storage means may comprise several memory chips, but it is preferred that it is made up of or comprises a single memory chip only. It is also within a preferred embodiment that the data storage means comprises a flash memory chip. It is preferred that the data storage means is secured to a memory printed circuit board.

The inner capsule may be formed of a tube with a main cylinder and a lid. According to one or more embodiments of the invention the inner capsule may be closed by a lid having one or more feed throughs, with at least one of said feed throughs being used for electrical signal connection from the outer surface of the lid to the interior surface of the lid. An interior lid printed circuit board may be arranged on the interior surface of the inner capsule lid and further be attached to a connector, and the memory printed circuit board may be attached to the connector, whereby electrical signal connection is established from the outer surface of the inner capsule lid via said at least one feed through, the interior lid printed circuit board, the connector, and the memory printed circuit board to the data storage means. Here, the memory printed circuit board may be hold in position inside the inner capsule by the connector at the lid end.

For embodiments of the invention having a memory printed circuit board, the memory printed circuit board may be hold in position at the bottom end inside the inner capsule by a support ring, which support ring may be arranged between the inner sidewalls of the inner capsule and the memory printed circuit board. Here, the support ring may be a plastic ring with two grooves for holding the memory printed circuit board.

The present invention also covers embodiments, wherein a top lid printed surface board is arranged on top of the inner capsule lid with electrical signal connection via the at least one feed through to the interior surface of the lid. It is also within one or more embodiments that electrical signal connection is established

between the electronic communication circuitry and the data storage means via said at least one feed through. Here, the electrical signal connection between the electronic communication circuit and the data storage means may further be established via a printed surface board arranged on top of the inner capsule lid.

It is within one or more embodiments of the invention that a duct is provided in the isolation material and the thermal mass composition for electrical signal wiring extending from the communication circuit board to the inner capsule. Here, the electrical signal wiring may extend from the communication circuit board to the top lid circuit board. A fire-wire cable may be used for obtaining electrical signal connection from the communication circuit board to the top lid circuit board. For embodiments having a mounting plate above the isolation material, an opening may be provided in the mounting plate for the electrical signal wiring extending from the communication circuit board to the inner capsule.

For the measurements of the inner capsule, it is within one or more embodiments of the invention that the inner capsule has an outer diameter below or about 60 mm and an outer length below or about 120 mm. Thus, it is also within embodiments of the invention that the inner capsule has an outer diameter in the range of 45-55 mm and an outer length in the range of 95-110 mm.

The present invention also covers embodiments, wherein the inner capsule has an outer diameter below or about 35 mm and an outer length below or about 75 mm. Thus, it is also within embodiments of the invention that the inner capsule has an outer diameter in the range of 25-30 mm and an outer length in the range of 60-72 mm.

For the measurements of the outer capsule, it is within one or more embodiments of the invention that the outer capsule has an outer diameter below or about 180 mm and an outer length below or about 320 mm. Thus, it is also within embodiments of the invention that the outer capsule has an outer diameter in the range of 165-170 mm and an outer length in the range of 280-300 mm.

The present invention also covers embodiments, wherein the outer capsule has an outer diameter below or about 150 mm and an outer length below or about

280 mm. Thus, it is also within embodiments of the invention that the outer capsule has an outer diameter in the range of 135-145 mm and an outer length in the range of 245-265 mm.

It is preferred that the thermal mass composition comprises gypsum or calcium sulphate dihydrate.

The present invention also covers embodiments, wherein a single cable holds the electrical wiring from the outside of the outer capsule lid to the inside of the outer capsule lid. This single cable may include the wiring for electrical powering the electronic communication circuitry.

The invention will be further described in the following with the aid of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a cross sectional view of an embodiment of a voyage data recorder according to the present invention,

Fig. 2 is a block diagram of a first embodiment of a printed circuit board holding electronic communication circuitry for communicating with the outside world of the data recorder of Fig. 1 ,

Fig. 3 is a block diagram of a first embodiment of a printed circuit board with data storage means for the data recorder of Fig. 1 ,

Fig. 4 is a block diagram of a second embodiment of a printed circuit board holding electronic communication circuitry for communicating with the outside world of the data recorder of Fig. 1 , and

Fig. 5 is a block diagram of a second embodiment of a printed circuit board with data storage means for the data recorder of Fig. 1.

DETAILED DESCRIPTION OF THE INVENTION

In Fig. 1 is shown a cross sectional view of a preferred embodiment of a hardened voyage data recorder 101 according to the present invention. The data recorder 101 holds a memory printed circuit board 102, which circuit board 102 holds data storage means in the form of a memory chip 103. The memory circuit board 102 is contained within an inner capsule 104. The inner capsule 104 has the form of a tube with a main cylinder part 105 and an upper lid 106. Feed throughs 107 are provided in the lid 106, whereby electrical signal connection can be obtained through the lid 106. For the data recorder of Fig. 1, a printed circuit board 108 is arranged on the top of the inner capsule lid 106, and a printed circuit board 109 is arranged at the interior surface of the inner capsule lid 106, with electrical connectors going from the circuit board 108 via the feed throughs 107 to the interior circuit board 109. A connector 110 is secured to the interior circuit board 109, and further being attached to the memory circuit board 102, whereby electrical signal connection is obtained from the top lid circuit board 108 to the memory chip 103.

In order to hold the memory circuit board 102 in position within the inner capsule 104, a support ring 111 is arranged at the bottom of the inner capsule 104 between the sidewalls of the inner capsule 104 and the memory circuit board 102. The support ring 111 is preferably made of a resilient material, such as plastic, with two grooves for receiving the memory circuit board 102. The support ring 111 is made of a resilient material and the grooves are not penetrating the ring 111. Thus, by having the memory circuit board 102 held in position by the connector 110 and the resilient ring 111 , the position of the circuit board 102 is maintained without giving too much tension to the circuit board 102, thus avoiding breakage of electrical signal paths of the circuit board 102.

For a first preferred embodiment, 6 feed throughs 107 are provided in the lid 106. The inner capsule 104 is preferably made of a stainless steel tube having an outer diameter of about 49 or 50 mm and a total outer length of about 102,5 or 107 mm. The inner tube diameter is preferably about 41 ,8 mm, giving a wall thickness of about 3,6 mm. The thickness of the bottom is about 7 mm, and the thickness of the lid 106 is about 28 mm. One ore more O-rings may be used to provide a sealed closure between the lid 106 and the interior of the main cylinder

of the inner capsule 104. The feed throughs 107 are sealingly closed around the electrical connections by use of a glass sealing to thereby obtain a sealed closing withstanding a pressure of 600 bar.

For a second preferred embodiment using USB interface, only 4 feed throughs 107 are provided in the lid 106, whereby the total dimension of the inner capsule can be diminished. Here, the inner capsule 104 has an outer diameter of about 28 or 29 mm and a total outer length of about 65 or 66 mm. The inner tube diameter is preferably about 20 mm, giving a wall thickness of about 3,9-4 mm. The thickness of the bottom is about 5 mm, and the thickness of the lid 106 is about 24-25 mm.

By using gypsum/calcium sulfate dehydrate as a thermal mass composition, it is possible to keep the temperature inside the thermal mass at approximately 100 ⁰ C during a fire incident. This is possible due to the release of water as long as the gypsum/calcium sulfate dehydrate is converted to calcium sulfate hemihydrate. The temperature of about 100 ⁰ C will not harm the memory chip 103.

A duct is provided at the upper shelf part of the thermal mass 112a for conducting electrical wiring 113 to the top lid circuit board 108.

For the first embodiment, the gypsum 112a, 112b has an outer diameter of 100mm and a total outer length of 190mm. For the second embodiment, the gypsum 112a, 112b has an outer diameter of 83mm and a total outer length of 160mm.

The thermal mass composition 112a, 112b is surrounded by a layer of isolation material. The isolation material is made up of a lower tube part 114, in which the thermal mass 112 holding the inner capsule 104 with the electrical wiring 113 is inserted, and an upper lid part 1 15 closing the tube part. A duct 116 is provided in the upper lid part 115 of the isolation for conducting the electrical wiring 113 through the isolation material.

For the first embodiment, the outer diameter of the isolation material is about 161 mm and the total outer length is about 270mm. For the second embodiment, the outer diameter of the isolation material is about 136mm and the total outer length is about 230mm.

A tube formed outer capsule 117 made of 2mm stainless steel surrounds the isolation material 114, 115, and a mounting plate 118 made of stainless steel is arranged on top of the lid 115 of the isolation material. The outer capsule 117 is closed by a lid 119, which has a connector opening 120 with a connector house 121 for feeding electrical wiring 122 from the outside of the outer capsule lid 119 to the inside of the lid 119. O-rings are used to provide a sealed closure between the connector house 121 and the electrical wiring 122, between the connector house 121 and the lid 119, and between the lid 119 and the outer capsule 117. The lid 119 and the connector house 121 are made of 4mm stainless steel. For the first embodiment, the outer diameter of the outer capsule tube 117 is about 168mm and the outer length of the tube 117 (not including the lid 119) is about 296mm, while for the second embodiment, the outer diameter of the outer capsule tube 117 is about 140mm and the outer length of the tube 117 (not including the lid 119) is about 256mm

The mounting plate 118 has two functions. First, the plate 118 functions as a stopper for the isolation material 114, 115 with two or at least two spacers 123 extending between the mounting plate 118 and the inner surface of the outer capsule lid 119 to keep the plate 118 in place on top of the isolation material lid 115. Next, the plate 118 holds a printed circuit board 124, which circuit board 124 holds electronic communication circuitry for data communication between the world outside to the voyage data recorder 101 and the memory circuit board 102. The circuit board 124 is secured to the mounting plate 118 at a distance above the plate 118 by 4 or at least 4 circuit board spacers. For the embodiment of Fig. 1 the spacers 123 are of stainless steel with a length of 19 mm and diameter of 4,2 mm, while the circuit board spacers, which are also of stainless steel with a diameter of 4,2 mm, have a length of 3 mm. Plastic sealant may be used to fill the potential space between the isolation material 114, 115 and the mounting plate 118.

Communication to the world outside the voyage data recorder 101 takes place via the electrical wiring 122, by which signals are transferred to the communication circuit board 124. A hole is provided in the mounting plate 118 for passing the electrical wiring 113 from the communication circuit board 124, through the isolation lid duct 116, through the duct of the thermal mass 1 12 to the top lid circuit board 108.

Fig. 2 is a block diagram of a first embodiment of the communication circuit board 124a holding electronic communication circuitry for communicating with the outside world of the data recorder 101 of Fig. 1 , when communicating via Firewire bus. The circuit board 124a holds power circuitry 201 supplied via 2 pairs, a Firewire driver circuit 202 supplied via 2 pairs CAT5 input cable, and a Firewire repeater transceiver/arbiter chip 203. The output of the PCB 124a is via a standard 6-pin Firewire Interface cable.

Fig. 3 is a block diagram of a first embodiment of the printed circuit board 102a with data storage means 103a for the data recorder 101 of Fig. 1, when communicating via Firewire bus to the communication circuit board 124a of Fig. 2. The circuit board 102a holds power circuitry 301 , Firewire PHY cable transceiver/arbiter 302, a Firewire to IDE controller 303 and a memory module 103a with IDE interface. The memory module 103a may be a STEC SLISCDxxxM-GM1UI module. Communication to the communication circuit board 124a is provided via the standard 6-pin Firewire Interface cable.

Fig. 4 is a block diagram of a second embodiment of the communication circuit board 124b holding electronic communication circuitry for communicating with the outside world of the data recorder 101 of Fig. 1 , when communicating via Ethernet. The circuit board 124b holds power circuitry 401 , a CPU 402 with Ethernet control circuitry, RAM circuitry 403, EPROM circuitry 404 and a USB Host controller 405. The power circuitry 401 is supplied via 2 pairs, and the Ethernet controller of the CPU 402 is supplied via 2 pairs CAT5 cable.

Fig. 5 is a block diagram of a second embodiment of the printed circuit board

102b with data storage means 103b for the data recorder 101 of Fig. 1 , when communicating via a USB interface to the communication circuit board 124b.

Here the circuit board 102b holds a single memory module 103b with USB interface. The single memory module 103b may be a SLUSCDxxxM-GU1 U module. Communication to the communication circuit board 124b is provided via the USB interface. When using the USB interface only 4 feed throughs 107 are needed through the inner capsule lid 106.

When comparing the above described embodiments of the new voyage data recorder according to the present invention with prior art voyage data recorders, then the new data recorder has a new memory design. While standard memory modules (e.g. 2.5" disc modules) may have been used for prior art data recorders, then single memory chip modules 103 may be used in the new data recorder. This enables a much smaller inner capsule 103 and then, consequently, a much smaller product.

For the new data recorder of the present invention, the inner capsule 104 may have an outer diameter of D=50mm and an outer length of L= 107 mm, which is significantly smaller than previously known designs.

For the new data recorder, the printed circuit board 102 holding the memory module 103 is much lighter than in the previously known design, and the circuit board 102 is held in position in a way where its movement is limited to an acceptable level without putting any stress on the circuit board 102. The circuit board 102 is supported by its connector 110 in one end and supported in the other end by a support ring 111 , made of a resilient material such as plastic, and having two groves.

For the new data recorder the outer capsule 117 may be made out of a 168,4 mm standard stainless tube, which is much smaller than for previous designs.

For the new data recorder, the communication circuit board 124 having electronics that receives the communication to the voyage data recorder 101 and transmits it to the inner capsule 104 e.g. a repeater, is located inside the main outer cylinder rather than in a special housing. The electronics is mounted on a mounting plate 118, which may have a diameter of 162mm, and which is glued to the inside of the outer capsule 117 during production using a fixture that will

ensure that it is correct positioned. The spacers 123 on the mounting plate 118 extend to the lid of to capsule 119 and ensures that isolation material is kept in position when the capsule is exposed to chock or vibration. Plastic sealant is used to fill the potential space between the isolation material and the mounting plate 118.

It should be understood that various modifications may be made to the above- described embodiments and it is desired to include all such modifications and functional equivalents, which fall within the scope of the accompanying claims.