THE Royal Hong Kong Police Force's marine division faces an uphill - or more appropriately up-wave - battle each time it sets off after smugglers and other sea criminals. Imagine trying to pursue a dai fei which boasts about 100 powerful outboard motors. Fortunately for the good guys, technology is helping the police catch up with the baddies. At the Science and Technology pavilion, the RHKPF reveals the latest advances in the key areas of navigation and anti-smuggling. A simulated bridge of one of the police's craft has been created to show visitors how the technology works. Perhaps the most interesting device is the Electro Optical Surveillance System which has an infra-red sensor head, processor unit, a set of moving mechanisms and a monitor unit. The sensor head is used to detect invisible infra-red rays which are emitted from objects and converts them into video signals to match the shape of the object - ideal for night-time hunting. The pictures shown on the TV monitor were recorded during anti-smuggling operations. Another ''smuggler buster'', is the Radar Bridge Master which comprises a transmitter, display unit and a scanner unit. The video signal on the TV monitor picks up either stationary or moving targets. There is not much point being in a boat if you do not know where you are or where you are going. Fortunately the sea police have both angles well and truly covered. The bridge is full of navigational aids, including: Auto chart table Nautoplot. An integrated navigation and steering system, this allows the ship's position to be plotted on to a sea chart. Gyro Compass SGB 100A. A compact master heading reference instrument, this gives a true north reference. It automatically shows the ship's heading, irrespective of the earth's magnetic fields. Speed Log. This is a speed meter to measure the velocity of a vessel through the water and total distance travelled. Echo Sounder. This supplies depth information which is recorded on paper and a digital indicator simultaneously.