How precision motors power defence solutions

Defence programmes are often early adopters of emerging technologies and many revolutionary systems depend on powerful precision motors. Electro-Mechanical Systems managing director Stewart Goulding explores their significance.

// D-Orbit plans to track debris from space using its recently launched In Orbit Now satellite carrier vessel. Image: D-Orbit

// D-Orbit plans to track debris from space using its recently launched In Orbit Now satellite carrier vessel. Image: D-Orbit

The defence sector is a valuable contributor to the UK economy, providing a large number of jobs and investing in several UK industries. The relationship is mutual, with advancements in industry benefitting the defence sector and vice versa.

In particular, powering electronic defence equipment, such as breathing apparatus and remotely operated vehicles, with high-precision motors aids the sector’s success. Let’s take a look at some examples.

Precise movements for ROVs

Remotely operated vehicles (ROVs) are used to carryout dangerous tasks or activities in hazardous environments. On land, ROVs may carry out missions such as exploration, mine reconnaissance or even explosive ordnance disposal.

ROVs can also be used in underwater environments to eliminate the need to endanger a diver or to reach areas that are difficult to access. Underwater, ROVs may carryout additional tasks, such as hull inspections and retrieval of lost equipment. ROVs feature robotic arms to hold equipment and handle explosives, and possess a rotating camera for the operator to see the surrounding environment and the taskbeing performed.

Using a compact, highly efficient yet powerful ironless rotor motor allows for precise and agile movements of the arms and camera, while adding minimal weight to the vehicle. A lower weight allows the vehicle to move through water or across rough terrain with ease, and in combination with the high efficiency, reduces the load on the onboard battery, which in turn increases the usable operating time of the vehicle.

// A computer-generated image representing space debris as could be seen from high Earth orbit, showing objects in geosynchronous and low Earth orbit. Image: NASA

Giving detection systems focus

Optical imaging systems used for intelligence, surveillance and reconnaissance applications require motors for zoom, focus, pan and tilt functions. Equipment that uses powerful, precise and compact motors will be able to perform quick and accurate camera movements, ensuring an image or video of a fast-moving subject such as an aircraft or ground vehicle can be captured without adding significant bulk or mass to the camera system.

Radar systems are also used to monitor the surrounding environment, using radio waves to determine the range, angle and velocity of moving objects or learn about the surrounding terrain. They can be used to detect aircraft, vehicles, ships, guided missiles and weather formations. Early detection provides time for preparation, whether that’s sheltering from a storm or using a smart sensor to redirect an oncoming missile.

Radars consist of many rotating components and a moveable dish to detect signals from all angles. They require high torque motors to power fast and responsive movements. The motors must also be durable to ensure they can withstand being exposed to extreme outdoor conditions. A motor fault or failure could result in missed signals, with potentially fatal consequences.

Powering wearable equipment

Defence personnel who are working in the field may encounter environments contaminated with dangerous gases or biological toxins. A powered air-purifying respirator (PAPR) filters a portion of the surrounding air to remove hazards and then delivers the clean air to the user.

It’s important that the motors used to power the filtering process are reliable, as a fault or failure could be life-threatening. Engineers designing a PAPR should choose motors that are trustworthy and efficient to ensure high-performance filteringwhen equipment is worn for a long time. A compact ironless rotor motor with very high efficiency, fast acceleration and very stable dynamic performance, such as the Faulhauber SR series, is an ideal choice for PAPRs.

Another potential example of wearable electronic defence equipment is powered exoskeletons. Exoskeletons are powered by a combination of electric motors, levers, hydraulics and pneumatics, which assist limb movement. Sensors are installed into the suit to record the movements of the user, with the information collected being fed to the electric motors that power the movements.

Motors used in exoskeleton suits must be lightweight to allow quick and agile movements, and powerful to propel the suit’s limbs forward.

Applications for exoskeletons in the defence sector are still in the development stage but are being trialled by several nations. Defence exoskeleton prototypes are showing the potential to allow users to go beyond their physical capability, performing with higher strength and endurance.

Exoskeletons may also protect the wearer from physical strain, which is a common problem in the defence sector. They could be used to support tasks such aslong-distance trekking, but the full potential of using these exoskeletons in a combat sense is not yet certain.

Motors used in exoskeleton suits must be lightweight to allow quick and agile movements, and powerful to propel the suit’s limbs forward. The motors must also have high precision to work to together to create synchronised movements.

Helping service robots take the weight

Robotic systems are not only beneficial as wearable exoskeletons. Defence service robots are also becoming more widely researched and deployed, with perhaps the most promising application being carrying equipment.

Defence personnel often have to travel long distances, whether they’re moving to a new base or performing surveillance over a large area. A loaded march is where defence personnel must move quickly over a long distance while carrying a significant load. This journey can be tiring and straining, particularly if performed in an extreme climate. In the desert heat, the use of loaded marches must be limited to avoid heat exhaustion, which can prolong the personnel’s journey.

In long-distance trekking robot dogs, such as those developed by Boston Dynamics, are advantageous. For example, the quadruped military robot BigDog was capable of carrying up to 330 pounds while remaining balanced over rough terrain. Although this project was discontinued as the robot’s gas-powered engine made it too loud for combat, research into producing similar robots that are all-electric and powered by micromotors could produce a quieter yet capable option for the defence sector.

The increasing complexity of global safety threats calls for more sophisticated defence technology. Electronic defence equipment designed with durable precision motors can perform with accuracy and reliability, helping to keep defence personnel safe.