Page 106 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition

94 CHAPTER 4 Vehicle Control and Simulation
Logic driven with goal orientation
Logic-driven vehicle control
DP system thruster control
Basic thruster control with autostabilization
Basic thruster control (RC or teleoperation)
FIGURE 4.1
Vehicle control from simple thruster control to full logic control with goal orientation.
4. Logic driven: “I am sitting in that same control room observing the ROV automatically navigating a series of waypoints while running a search pattern when I observe Mr. Nasty anchored to the bottom. The ROV automatically operates [or I do the deed remotely] the fire control system. RIP Mr. Nasty.”
5. Logic driven with goal orientation: “I upload goal instructions (i.e., Find and neutralize
Mr. Nasty.) for layering on top of the basic thruster controls, then launch my ROV [or AUV] into the morning waters of the harbor. I am at the pub in the evening sipping a beer when I receive a text from the ROV/AUV saying, RIP Mr. Nasty.”
As one of the basic premises of ROV control is the “R” (meaning “Remotely”), direct control will not be examined. RC mode normally occurs at the surface while the operator is directing (typi- cally) an ROV to a location whereby visual contact is made using the vehicle’s camera for transi- tioning from RC mode to teleoperation mode. Practically all ROV operations are performed via teleoperation (e.g., visually, acoustically, magnetically, etc.—in other words, any sensor feedback from the vehicle may be used for the sense portion—sense/plan/act). New vehicles, however, layer on levels of automation from basic auto-heading/depth/altitude control to full dynamic positioning (DP) with waypoint navigation. The top level of Logic Driven with Goal Orientation is addressed in more detail in Chapter 23 as this method of control is clearly where the technology is destined. Figure 4.1 depicts the levels of vehicle control from simple to complex.
4.1 Vehicle control
In this section, the levels of vehicle control will be examined, ranging from the basic joystick con- trol of thrusters for vehicle mobility to full logic-driven vehicle management. There are many fac- tors driving control decision making including (but hardly limited to) schedule, cost, environment,
Level of complexity