Fast-Acting, High-Reliability Acoustic Release
The ARC-1XD ‘extended duration’ acoustic release is specifically optimized for the operation and remote recovery of large inventories of underwater equipment. The release is simple in design and use. It provides the operator with real-time status feedback, and then uses a very fast acting mechanism to reliably recover the payload. Patent #US 7138603 B2
How it Works
Arm: The release is armed prior to use by inserting a small length of nickel-chromium wire which constrains a lever. The pictures on these pages show various applications where the release is rigged to free a float for recovery of fishing or scientific gear, or used to drop an anchor that allows an instrument package to free float to the surface for recovery.
Test And Deploy: The package is now submerged next to the boat, or placed in a water filled test tub on deck. A command from the deck unit confirms contact by interrogating the release ID (4096 available), tests the device and registers the GPS location. The instrument package is now dropped to the sea floor and the boat can proceed.
Interrogate: As the boat approaches the GPS location, the deck box interrogates and ranges to the ARC-1. Battery status information is returned and the distance measurements are used to position the boat close to or directly above the release. Even if an instrument moved, ranging allows the boat to be positioned for rapid recovery – in particular useful in heavy seas.
Release: Upon command, the ARC-1 energizes the nickel-chromium wire with a safe low-voltage but very high current pulse. It vaporizes instantly, the lever opens and the instrument package or a buoy rises to the surface. The ARC-1 also confirms released status.
The simplicity of the mechanism and its fast action lets you get your gear back fast and reliably, allowing you to move on to the next site and servicing many units in a working day.
Instant Release Ensures Unparalleled Reliability
The ARC-1XD release mechanism is based on the vaporization of a nickel-chromium wire by means of a very high current electric current. The wire is strung between two sturdy posts, constraining a simple level arm. Upon vaporization, the lever arm is set free and opens typically by the buoyant force of the instrument package or a buoy that is released to the surface.
The mechanism is very fast acting. Overall, time from issuing the release command until trigger of the release is a few seconds. The wire vaporization itself lasts just a few thousands of a second. Fast action enables recovery of many instruments in a day at sea. This contrasts releases based on the electrolytic erosion of a link, a process that takes 5 to 30 minutes.
Works in sea and fresh water alike and release process not inhibited by any wire fouling concern. Electrolytic erosion releases do not work effectively in fresh water or may be inhibited by link fouling.
Very simple with only a single moving part. Upon wire vaporization, the lever arm is virtually guaranteed to open when used as instructed. This compares to motor and solenoid driven releases that have multiple moving parts and are susceptible to jamming due to marine fouling.
Non-Corrosive Hardware & Low Power Consumption
ARC-1XD is manufactured entirely using non corrosive materials. The housing is a tough and ductile Delrin, a slippery, shatter proof and fouling resistant material well proven in underwater systems. The metal hardware is entirely titanium, eliminating any corrosion concerns. This eliminates other devices that may use crevice corrosion susceptible stainless steel, or anodized aluminum that is subject to pitting.
The ARC-1XD also requires minimal power, and a single D-size Lithium battery powers the processor and acoustic receiver for mission durations of up to two years. The sonar transmitter and release mechanism are powered by a set of 4 AA alkaline cells which are electrically disconnected from power until the interrogate and release sequence has been initiated. A battery pack lasts through about 50 release cycles. This allows the ARC-1 to be re-deployed without many times and supporting quick turn-around of the equipment when servicing a large number of deployed units or sets of fishing gear on a regular basis.
The endurance of the ARC-1 is proven through lengthy and repeat deployments of numerous hundreds of the devices owned by our customers. At this time, the cumulative field history of the ARC-1 is likely in excess of 1000 years.
Fast and Efficient
At sea, the ARC-1XD is serviced quickly and easily.
The batteries last for a cumulative deployment of up to two years and 50 release cycles. When servicing a large set of gear repeatedly over a season, a recovered release can be re-deployed without changing batteries. Instead, in many cases it is sufficient to service batteries in between seasons.
Re-arming of the release is as simple as a quick hose down (if necessary), and the securing of a new 25mm (1″) length on nickel-chromium between the posts. The only tool needed are some snips and a small Allen wrench. The cost of wire replacement is pennies.
Instant acting release mechanism with a single moving part
Dimensions 57mm (2.25”) D x 550mm (21.5”) L
Buoyancy: slightly negative
Capable of supporting a buoyant force of 18kg (40lbs) with a 2x safety factor
Depth rating: 300m (1000 ft)
Battery endurance two years and 50 release cycles
Supports multiple deployments without battery change
Non-corrosive Delrin & titanium design
Transponder functions support ranging to the units
Operating frequency: 34-42kHz
Catch and Release Applications
Servicing and recovery of scientific instruments such as underwater acoustic recorders and pinger receivers. The ARC-1XD is a popular device for the release of such devices as Vemco pinger receivers and C-POD acoustic detectors. The ARC-1XD is also an ideal release device for our own upcoming microMARS acoustic recorder.
Remote release of recovery buoys of lobster and crab pots. The ARC-1XD is used in high quantities by fishermen in New South Wales (Australia) to service lobster pods. Using the release keeps pots secure on the sea floor without a vulnerable surface marker line and allows the fisherman to easily access their catch whenever needed.
Remote trigger or operation of any underwater mechanical device.
Cronulla Fisheries Research Center, Australia
(during their early tests of the ARC-1 for remote release of recovery buoys for rock lobster pods – the tests were successful and by now the releases are in regular use by several fishermen)
“The next day we were able to make a few releases in a bucket of water and everyone was impressed. I connected the release to a rope bag in a rather crude way but it worked and we were able to recognize its potential by releasing a float from the rope bag in a swimming pool. Since then, we have shown the fishermen the demonstration and discussed in detail how we move forward. At the moment one of the releases is with one of the fishermen so he can determine the method of attaching the release to the rope bag and the rope bag to the trap. Everyone involved is impressed and somewhat surprised at the level of engineering of the system and so far we don’t expect any problems.”
“So far, we have had a total of 9 successful deployments and releases of our system using the ARC-1R Remote Release. Our entire system, including the release worked flawlessly.”
“Everything went really well, few flaws in the way I designed the trap and buoy retainer, but we worked them out early on – our deployment rig needed a quick mod after we lost the first trap due to the rocking of the boat in the swell, other than that, things went off without a hitch. We put 26 traps down and got all our gear back – a success.”
Corresponding DoD TRL: N/A
Description: This product has endured over 50 missions successes in the field. A product with this badge represents the best of Desert Star; only the most robust and refined products are approved for the gold star.