March 2018
rapidCAST User’s Guide
Page
2
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
The rapidCAST delivers a probe to a user-specified target depth while the vessel is underway, and re-
trieves the probe automatically. Using an entirely new active tension management system, payout behav-
ior is precisely controlled to ensure the probe depth is known at all times - even without a conducting ca-
ble! Data transfer is achieved using an automated Bluetooth connection.
rapidCAST provides:
•
A Tension Control System that allows the probe to fall freely under the influence of gravity
even when the probe is tethered to the winch.
•
Line tension is measured in real-time, and the rotation speed of the spool is quickly modulated
to minimize tugging on the probe.
•
If tension rises above the setpoint, the spool speeds up, and if tension falls below the setpoint,
the spool slows down until equilibrium is restored.
•
The Tension Control System prevents the ship from dragging the probe, and ensures that the
probe falls freely despite surface disturbances such as waves, swells, heaving, pitching, and roll-
ing.