The propulsion system consists of 8 ducted fans or thrusters that
are used to translate and rotate Ranger NBV in the neutral buoyancy
environment. Figure 2-3 shows the layout of the thrusters on the
Figure 2-2 The top y thruster
Figure 2-3 Thruster layout on the Propulsion Module
An early design decision was that the thruster layout should be arranged such that the vehicle would have more power for translating forward and reverse than side to side, or up and down. This would allow the it to travel rapidly from one task location to the next. Thus Ranger NBV has 4 thrusters directed along the x-axis. Not only do these provide x translation, but they also provide pitch, and yaw actuation. The 2 y-thrusters provide translation along the y-axis, along with half of the roll capability. The 2 z-thrusters provide translation along the z-axis along with the other half of the roll capability.