AC-CESS and their engineering partners at All Oceans looked at existing small ROV technologies and set to improve upon them. Principal design drivers were size, mobility, robustness and overall portability.

The AC-ROV is a full five degrees of freedom underwater video camera and sensor platform. This manoeuvrability is essential as other underwater inspection vehicles do not have the mobility to work in confined spaces.

4 horizontal thrusters operate together to power the AC-ROV forward, back and sideways. Their “vectored” arrangement is like having 4 forward and 4 side, or lateral thrusters. This is the thruster set up on the vast majority of serious commercial ROVs because lateral power and speed is as important as forward power and speed. One is used to get you to the target, the other is for keeping you face onto the target. More often than not any current at a target will not be head-on, but SIDE-ON, so serious inspection requires serious lateral flight capability. This is why the AC-ROV can fly as fast sideways as it can forward and back, or more importantly, hold station in a given current coming from any direction. There are also 2 vertical thrusters for up, down and tilt control.

To make the most of the AC-ROV’s manoeuvrability, the system uses a completely intuitive 3D controller with a single handed grip that can be moved in any direction, rotated and tilted. The AC-ROV responds by moving in the same way that the grip is moved. Controlling more movements than any single-handed joystick, it is still easier to use, simply because it doesn’t require brain power. The controller incorporates an array of powerful flight assist functions:

Flight Freeze / Flight Un-freeze / Progressive Forward Flight, Vertical Trim and Tilt / 3 stage Power Increment / Camera switching.

With a “fly through” size of 190mm and a “drop through” size of 210mm, the AC-ROV can get into seriously small spaces. The unique AC-ROV thrusters do not have central shafts and the inward pointing blades do not meet. Apart from being very resistant to fouling, they provide full bore equal thrust in both directions. This is not the case for shaft mounted thrusters which normally have a motor right in the middle of the flow path and a shaft just waiting to foul up. The design results in an overall power to weight ratio 50 -100% greater than other small ROV. All these market leading attributes are delivered in an extremely robust, reliable, modular design. Its inherent strength and serviceability means that the AC-ROV keeps coming back for more.

Model	100
Size	203mm x 152mm x 146mm (8" x 6" x 5.75")
Weight	3kg (6.6lbs)
Depth Rating	100m sw
Camera	Colour CCD, 800 Line X 0.1 Lux, Focus = Fixed 100mm - Infinity
Thrusters	6 thrusters (4 x horizontal vectored, 2 x vertical)
Lights	4 camera tracking LEDs (variable intensity)
Control	Field proven, single handed 3-D grip controller (LH or RH)
Monitor	145mm (5.6") colour TFT LCD in waterproof housing
Video Overlay	Date, Time, Power Setting, (Depth optional)
Sensors	Temperature, Humidity and Water Ingress
Tether	Options to 40m with Tether Deployment System
Tether Connection	Back as standard, with Top and Bottom options
System Power	300 watt (0.4hp)
Payload	200g (8oz)
Inputs	90/260vac x 47/63Hz auto ranging
Outputs	Composite Video
Handling	18kg (40lbs) complete in one hand carry case 490mm x 380mm x 190mm (19.25" x 15" x 7.5")
Integrated Options	USBL Positioning & Tracking Rear View Camera and Light Depth Sensor 2 Function Manipulator - Grip and Continuous 2 Way Rotate - 2 and 3 jaw grips Slip Ring Tether Deployment System Thickness Gauge Laser Scaling Roller Kit
Other Options	Custom Tether Deployment Systems Alternative or Additional Monitors Tethers to 120m
Notes	All ROVs suffer from tether drag. It affects flight control and the ability to reach a target and is more noticeable with smaller ROVs. Simple dive planning can help this to work for you. Sometimes fixing a weight a distance behind the ROV to take some of the strain works well. More sophisticated still are Tether Management Systems. An ROV manufacturer that works closely with customers and operators will be able to help. Touch buttons on the 3-D controller provide powerful “Flight Assist” functions. These are; Flight Freeze / Flight Un-freeze / Progressive Forward Flight / Vertical Trim and Tilt / 3 stage Power Increment / Camera switching. The tether cable and connectors are completely field serviceable. Any damaged cable can be cut out and any remaining serviceable cable reterminated and used again. No need for cable moulding services. Connect any type of video recording device to the system for recording and data logging. A computer is not required for normal operation nor included in the supply.