Computerized remote control has come of age with the new generation of microcomputers. The use of microcomputers and an umbilical data communication tether between surface and remote vehicle, in a new concept already operational in our RECON V® and other remote controlled vehicles, eliminates hardwiring complications and simplifies automatic routines. Under this system the surface microcomputer and vehicle microcomputer communicate with each other by multiplexed signals carrying analog and digital data. The entire process between the command and execution is transparent to the operator at the surface console. He selects a command function or moves a joystick and sees the response displayed appropriately on his console. Continuous surveillance of sensor information by the vehicle microcomputer facilitates algorithmic performance in such automatic functions as auto-heading and autohover where delta values are continuously sampled and are used to vary thruster output. This paper provides a software-oriented discussion of currently operational data and control system and points out such advantages as:
Reduced umbilical diameter by using less wires
Flexible design of automatic closed-loop control for heading, hover, depth, altitude, etc.
Informative video display screens for better operator interface
Continuous surveillance for alarms, operational interlocks, and automatic shutdown procedures
Automatic prelaunch tests and continual self-checking
A log of all important commands and sensor measurements recorded.
As oil exploration and production move into deeper waters, remote vehicles are doing an ever-increasing share of underseas work. This is true not only for reasons of safety in a harzardous environment but also because it is more economical and requires less space than dive complexes or manned vehicles.
These vehicles must of course perform a variety of functions and respond reliably to remote commands. The usual means to ensure this has been the use of an umbilical tether containing separate wiring for each assigned function. In multifunction operations, this has meant large diameter umbilicals with increased drag, larger handling systems, and slip-ring complications.
New technology has provided a much better solution the microprocessor, a small one-chip computer. The resulting remote-vehicle command system uses a microprocessor based system in a surface command console and a similar computer system in the vehicle, communicating in a multiplexed fashion through an umbilical data link carrying both analog and digital data. Other hardwired multiplexing systems exist, but they have not been cost competitive for most industrial applications.
This system greatly reduces the number of wires necessary, making the umbilical much smaller, lighter, less costly, and reducing drag. With the implementation of a computer-based system, many additional functions can be introduced to assist the operator in overall performance. These may include closed-loop automatic routines, in the vehicle such as automatic heading and automatic hover, and video displays in the surface console that present the data in engineering units and are updated continuously. Additionally, routines can be added to indicate to the operator that a particular value has reached an alarm-limit condition.
