Fig. 8.29 Motor conlfol unit for PC-U. 



lateral propulsion from two thruster motors 

 of 2 hp each. All motors are pressure com- 

 pensated and reversible, and speed control is 

 continuously variable throughout its range. 

 An electrically-powered rudder may be 

 moved 35 degrees left or right by a 20-rpm, 

 reversible gear motor enclosed in a pressure- 

 compensated box. To control these devices 

 STAR III has both fixed and portable con- 

 trols. The fixed controls (Fig. 8.31) and push- 

 buttons are mounted on the starboard side. 

 To operate the thrusters the buttons must be 

 constantly depressed, if not, they return to 

 stop (so-called "deadman" control). There are 

 no provisions for rudder maneuvering on the 

 fixed controls. The portable control box has a 

 joystick for forward-reverse and left-right 

 control, a separate lever for vertical thruster 

 control and two toggle switches for left/right 

 rudder control. The thruster controls provide 

 for continuously-variable speed and must be 

 reset to neutral or stop. A rudder angle 

 indicator is incorporated into the portable 

 control box. It may seem a small matter 

 whether or not a button remains in when it's 

 been pushed or returns to its "stop" position 



when released, but it must be remembered 

 that if a deadman-type control is used then 

 the operator can do nothing else with his 

 hands while pushing the button. In a small 

 submersible, where the crew consists of one 

 or two people, a multitude of recurring and 

 concurrent tasks is required of these limited 

 resources. Such demands on the occupants 

 must be considered in designing control de- 

 vices. 



BEAVER: 



International Underwater Contractors' 

 BEAVER receives all maneuvering capabil- 

 ity from three, 5-hp each, reversible, pres- 

 sure-compensated, DC motors. Control of 

 these motors, which are rotatable through 

 360 degrees in the vertical, is through a 

 primary and backup system, both of which 

 are hand-operated and fixed. BEAVER^s pri- 

 mary control system possibly typifies the 

 most one can do with one hand in vehicle 

 maneuvering, without requiring the assist- 

 ance of a computer. Both control system 

 components are shown in Figure 8.32, and 

 the primary control system is shown in Fig- 

 ure 8.33. At operating depth with the joy- 

 stick neutralized and motors stopped, the 

 ballast control buttons bring BEAVER to 

 neutral trim. Forward or reverse motion is 

 obtained by pushing the joystick forward or 



-BOW TKBUSTEI** 



# 



Hi 



Fig. 8,30 The portable control box for V0L-L1 Designed and built by Perry 

 Submarine Builders. (Perry Submarine Builders. Inc.) 



400 



