Figure 1: The prototype lifting system, known as C-HOIST*, deployed from the icebreaker USCGC Healy.
BioHOIST, the Biospherical Hauler for Optical In Situ Technologies, is a device for lowering and retrieving profiling optical instrument systems. Figure 1 shows the prototype system, called C-HOIST* in a NASA TM (Morrow et al. 2010) prior to commercialization, deploying a custom aluminum IOP package.
Typically, BioHOIST is davit-mounted for easy use from vessels both small and large. BioHOIST is based on a light-duty commercial "pot puller" (model STP-2100 manufactured by Quality Products NorthWest, LLC, Seattle, Washington). It is equipped with a stainless steel self-grip sheave, and a 2.1 HP, 12 VDC electric power head. It has a 300 lb capacity. The gearbox assembly, which is part of the power head unit, is an extremely strong and reliable unit.
The sheave design eliminates the need to thread the line (or cable) through complicated idler wheels and pulleys. The line is simply laid into the sheave and around the idler wheels. A light downward pull seats the line between the rubber lined sheave, which grips the line for both paying out and hauling in. The sheave line capacity is 0.25–0.75 in. Because the line is not wound onto a drum by the power head, the line can be as long or as short as desired. There is no line length limit, and the device will pull line as long as the power source is available. The unit is typically operated using a 90 Ah lead-acid battery (not supplied). In this configuration, approximately 25, 6 min casts can be performed before the battery needs recharging.
BioHOIST is shipped with a control unit that attaches to the deck box controller to enable deployments at user-selectable speeds, which may vary during a cast. A brake switch enables motor torque to keep the sheave stationery whenever desired.
* Cable Hauler for Optical In Situ Technologies. For the complete description, click herefor the NASA Technical Memorandum chapter.