Remote-operated Unmanned Ground Vehicles (UGVs) provide the ultimate in capability and protection by removing human operators from scenarios where failure is expensive in terms of human life and property. Developed to operate in hazardous environments, the majority of UGVs offer payload modularity, deploying the latest military-grade technology to offer versatile and cost effective deployments with maximum flexibility.
Typical applications include response to new terrorist threats, enabling Explosive Ordnance Disposal (EOD) professionals to respond to Improvised Explosive Device Disposal (IEDD) at a safe distance. UGVs are also deployed for Conventional Munitions Disposal (CMD), ground surveillance, gatekeeper/checkpoint operations, urban street presence, and to enhance police and military raids in urban settings. Here UGVs can be used to "draw fire" and minimise the risks to military and security personnel by providing real time intelligence and increased situational awareness.
Further development of more compact form factor units has lead to the introduction of Small Unmanned Ground Vehicle (SUGV). These are lightweight, portable UGVs which further extend the application of the technology into more restrictive environments such as urban centres, culverts, tunnels and caves.
As deployments increase in operational ‘hot zones’ where the threat to the operator is potentially high, there has been a drive to move away from UGV actions being determined by an operator within visual range of the unit. Instead remote use of sensors, such as digital video cameras, is preferred, with control provided by the human operator via a secure communications link. The provision of ‘best quality’ imaging ensures that the UGV can be accurately controlled, and provide extensive manoeuvrability when negotiating difficult or dangerous obstacles and terrain. It is also particularly important when the UGV is needed for close manipulation work which demands precise control of the robot, including pan, tilt and zoom on a camera head to ensure a full range of vision.
Delivering high quality video and remote control via a radio link within form factors increasingly limited by size, weight and low power demand requires bespoke design and manufacturing. Low latency, of 100 milliseconds or less is a prerequisite for accurate reaction to command at a speed applicable to operations, while still delivering reliable signal and quality of video in tactical scenarios where high density radio traffic can be common.
Wood & Douglas creates rugged, compact, low power, surveillance and reconnaissance packages with Digital Video for Moving Objects (dVMo). Delivering a radio telemetry data link at 50 milliseconds, ensuring real time control of the UGV, Wood & Douglas provides for higher video image quality over greater physical range, whilst ensuring immunity from accidental and intended interference and interception.
The demand for higher quality imagery is met by creating multilevel modulation using digital signal processing (DSP) techniques. By creating Diversity Operation packages with two receivers, Wood & Douglas dVMo receivers compare and select the best video data packet, processing it to ensure high quality performance from the radio link. The use of diversity receiver topology enhances the effectiveness of the hardware, enabling high quality video, audio and data signals to be carried via radio for UGV applications. These enhancements also help drive improved reception on the antenna which can be limited as many UGVs will operate close to the ground or horizon.
The radio links - single direction from the UGV dVMO and bi-directional from the UGV radio module - are both packaged into a single, intrinsically safe box less than 40cms deep. The architecture is then defined and tailored based upon the operational range, power and frequency of the package. A wider range of frequency is a particular demand, especially for military and homeland security, where crowded frequency spectrum creates increased potential for both in and out-of band interference.
This need places demands on radio module performance, so Wood & Douglas ensures optimum receiver sensitivity across a range of outputs and a wide choice of frequency variants. The radio modules address this challenge by providing synthesised frequency agility to provide cost effective, high-quality radio transceiver packages which reduce the need for hot and bulky power amplifiers to boost the dVMo transmitter source.
This ability to reduce heat and extend power consumption is critical for the latest generation of SUGVs where power, space and weight considerations impact operational performance.
- Low latency radio links for pin point accurate control
- dVMo video for high quality visual assessment and manoeuvrability
- Wide range of frequency and diversity for secure command and observation