Manta
(2019)
Manta is a man overboard recovery device capable of launching a loop of rope and two inflatable slings over 100 feet. This prototype was developed over the course of three months by a team of 22 students for MIT’s capstone product design class. My role in this project included ownership of the system CAD, directing the mechanical design and fabrication strategy, as well as helping the team create technical content for our product launch.
Video demonstration of Manta’s alpha prototype in action. Testing was performed in Boston Harbor retrieving marker buoys and rescue manikins.
Manta is packaged in a water-tight case that can be mounted to boat rails or stored in a dock house.
The entire system is neatly packed so that it can be quickly deployed in emergency situations.
Manta features two projectiles that are offset from each other at a 15-degree angle. The projectiles diverge from each other after launch and create a perimeter of rope around the person to be rescued.
Manta’s two projectiles can carry a loop of rope far enough to encircle an individual up to 100 feet away. After contacting water the projectiles automatically inflate and serve as flotation devices.
Animation of Manta’s firing mechanism. After the trigger is pulled and the slide is released, the firing pins strike black powder charges that propel the projectiles forward. The charges are the same ones that are used in commercial powder actuated tools for driving fasteners into concrete.
Detail of the trigger assembly showing the trigger in red, trigger safety in green, and slide catch in purple. The slide catch provides additional leverage for the trigger pull as well as ensuring that the trigger does not move while the firing mechanism is being cocked back. (see animation above)
Trigger mechanism disassembled after field testing. Our prototype parts were fabricated from standard 1020 cold-rolled steel. A proper production version of this assembly would feature hardened parts for better wear performance as well as a coating for corrosion resistance.
The projectiles need to have enough mass to be able to pull rope behind them during flight without slowing down. Our team took advantage of this constraint by having that mass serve an additional function that transforms the projectile into a flotation device.
Each projectile includes an inflatable sling wrapped around a water sensitive inflation mechanism. The inflation mechanism is stripped from an off-the-shelf life preserver that punctures a CO2 cartridge after an internal salt capsule has dissolved in water.
The inflatable slings offer the person being rescued something to hold on to while they’re being pulled towards safety. The slings are made of a bright TPU fabric that is heat welded along its seams for an airtight seal.
