Defence

Strength through safety-critical systems

Robust and precise drive solutions for safety-critical defence systems

Reliability under extreme conditions

Defence systems must function reliably even under exceptional conditions. High accelerations, severe vibrations, shocks, fluctuating torques and extreme temperatures place particular demands on the drive technology used.

Clutches and brakes can perform vital functions in vehicles, automated systems, observation and positioning equipment, and other safety-critical applications.

They must transmit forces safely, switch drives precisely and hold moving assemblies in defined positions.

It is not only performance during normal operation that is crucial. Behaviour in the event of a power failure, operator error, an emergency stop or an unexpected load must also be taken into account. A reliable component supports an overall system that remains controllable even under difficult conditions.

When reliability is not an option, but a prerequisite

Mönninghoff components can be used in various areas of defence systems, for example

  • in military vehicles
  • in automated and remote-controlled systems
  • in positioning and swivelling mechanisms
  • in observation and sensor systems
  • in lifting, locking and retaining mechanisms
  • in drives for auxiliary units
  • in inspection and test systems for safety-critical components
  • in mobile and stationary defence installations
  • in drives with high demands on robustness and compactness
  • in systems with limited installation space and high power density

The specific motion task can vary considerably. A vehicle drive must cope with varying loads and severe vibrations. A positioning device requires precise power transmission and a secure holding function. An automated system must react quickly and reach a defined state in the event of a fault.

What all these applications have in common is that reliability, safety and robustness go hand in hand. Drive technology must not become a source of uncertainty.

Requirements for clutches and brakes

Defence systems place particular demands on drive components

  • High reliability The components must function reliably and be designed for their intended service life.
  • Robustness against vibrations and shocks Mechanical stresses must not impair function to an unacceptable degree.
  • Variable torques Loads and operating conditions can change rapidly and significantly.
  • High switching accuracy Drives and assemblies must be capable of being connected or disconnected in a defined and reproducible manner.
  • Reliable holding function Positions must be held reliably even during standstill, malfunctions or power failures.
  • Short response times In the case of dynamic and safety-critical movements, a rapid response can be crucial.
  • Compact design Limited installation space and high power density require a tailored design.
  • Low power consumption Mobile and self-sufficient systems benefit from energy-efficient components.
  • Temperature resistance The system must continue to function reliably within the specified temperature ranges.
  • Overload protection Drives, gearboxes, shafts and connected assemblies must be protected against incorrect loading.
  • Long service life The components should operate reliably even under high loads and during prolonged periods of use.
  • Ease of maintenance Inspection, maintenance and replacement must remain plannable under the specified conditions.
  • Traceable quality Design, manufacture and testing must be documented and traceable.
  • Seamless integration Clutches and brakes must integrate seamlessly into the mechanical, electrical and safety-related architecture.

The challenge lies in combining high performance with predictable behaviour. In this context, ‘robust’ does not simply mean larger or heavier, but rather designed to suit the specific system requirements.

Shifting, transmitting, maintaining safety

Mönninghoff develops clutch and brake systems that are tailored to the torque, speed, load cycling, environmental conditions, shift frequency and installation space of the respective defence system.

Electromagnetic multi-disc clutches

Electromagnetic multi-disc clutches are suitable for frequent shifting operations and variable torque requirements. They can be used where drive functions need to be reliably engaged or disengaged under varying operating conditions.

Possible applications include

  • engaging and disengaging auxiliary drives
  • connecting the engine, gearbox and output shaft
  • shifting between vehicle and auxiliary drives
  • Applications with varying loads and speeds
  • frequent engagement and disengagement within limited installation space
  • drives with high demands on service life and robustness

A suitably designed multi-disc clutch can combine reliable torque transmission with a compact design. When designing the clutch, torque, speed, engagement time, heat generation and environmental conditions must all be taken into account.

Electromagnetic toothed clutches

Electromagnetic toothed clutches enable defined, positive-lock engagement. They can be used where high torques need to be transmitted precisely and drive stages or assemblies need to be synchronised with as little play as possible.

Typical applications include

  • shifting drive stages
  • synchronising positioning and swivelling movements
  • activating and deactivating auxiliary functions
  • positive-lock locking and positioning tasks
  • applications with high requirements for low rotational play
  • systems with frequently changing operating states

The positive-lock connection ensures a clear switching state and defined force transmission. This is particularly relevant when an assembly must remain exactly in position after switching or operate in synchronisation with another drive.

Electromagnetic tooth brakes
Electromagnetic tooth brakes can hold loads securely and precisely in a defined position. The tooth-retention principle ensures a backlash-free holding function and can provide a compact solution for safety-critical movements.

Possible applications include

  • holding swivel and positioning axes
  • securing lifting and locking mechanisms
  • positioning sensors or monitoring devices
  • holding positions during standstill and maintenance
  • securing assemblies in the event of a power failure
  • emergency stop and safety functions
  • supporting redundant holding concepts

During design, the holding torque, switching time, positioning accuracy, load direction and safety concept must all be considered together. It is crucial that the brake is suited to the actual motion task and the system architecture.

Overload and protection functions

In mobile and safety-critical systems, blockages, impacts or unexpected load peaks may occur. Depending on the application, overload and protection functions can help to limit the flow of force or protect drive components from consequential damage.

Possible functions include

  • limiting excessive torques
  • protecting gearboxes, shafts and bearings
  • relieving the drive in the event of a jam
  • the controlled disengagement of the power transmission
  • the reduction of consequential damage in the event of malfunctions
  • supporting a defined response in the event of a fault

The specific protection function must be assessed in conjunction with the risk assessment and the overall system design. A protective component can only provide reliable support if its tripping behaviour, reset and restart procedures are clearly defined.

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Robust drive technology for safety-critical tasks

Whether for military vehicles, automated systems, positioning equipment, sensor technology or test benches: Mönninghoff develops clutches and brakes for applications where precision, robustness, reliability and compact integration go hand in hand.

Are you developing a new defence system, modernising an existing drive system, or looking for a reliable solution for shifting, holding and overload protection? Talk to our experts about torque, speed, load cycling, environmental conditions, safety functions and installation space. Together, we’ll develop drive technology that always performs reliably when it matters most.

Tried-and-tested technology for safety-critical systems

Reliability starts with the design

Defence systems often have to operate under conditions that are not part of everyday life in standard mechanical engineering. Shocks, vibrations, temperature fluctuations and variable loads have a direct impact on the mechanical components and drive systems.

For this reason, the following points, amongst others, should be taken into account during the design phase

  • Torque and speed
  • Acceleration and deceleration
  • Inertia of the moving assemblies
  • Load cycling and shock loads
  • Vibrations and potential resonances
  • Temperature range and temperature fluctuations
  • Humidity, dust and other environmental influences
  • Switching frequency and expected operating cycles
  • Desired holding and positioning accuracy
  • Rotational play and torsional stiffness
  • Behaviour in the event of a power failure and emergency stop
  • Requirements for overload protection and fault response
  • Available installation space and connection geometry
  • Weight and power consumption
  • Requirements for control, sensor technology and diagnostics
  • Maintenance, testing and traceability

Mönninghoff develops bespoke solutions that can be tailored to the specific system task and integration into the overall architecture. The focus is not only on the load-bearing capacity of an individual component, but on the reliable operation of the entire system.

Defined states for critical situations

In safety-critical applications, the system’s behaviour in the event of a fault is crucial. What happens in the event of a power cut? How is a moving assembly held in place? How does the drive react in the event of a blockage? How can the system be safely reset and returned to operation?

Depending on the application, the following functions may be relevant

  • mechanical holding independent of the running drive
  • safe disconnection or limitation of the force flow
  • controlled deceleration in the event of faults
  • monitoring of switching, braking and holding states
  • Integration into redundant safety concepts
  • Protection against overload and incorrect operation
  • Defined reset following a fault
  • Safe restart
  • Documented testing of safety-related functions

The specific safety function must be assessed and validated in conjunction with the overall system, the control system and the risk assessment. When it comes to safety-critical technology, a clear status is better than a big question mark.

Early validation for maximum reliability

In demanding defence applications, prototypes and functional models can help to assess the behaviour of drive components at an early stage. This allows potential weaknesses to be identified before series production begins.

Possible test points include

  • Switching time and switching reliability
  • Holding torque and holding accuracy
  • Behaviour under varying torques
  • Response to overload and blockage
  • Function during power failure and emergency stop
  • Behaviour under vibrations and shock loads
  • Temperature fluctuations and thermal stress
  • Endurance testing and wear
  • Behaviour under varying environmental conditions
  • Integration into mechanical systems, control systems and sensor technology
  • Reset and restart
  • Testing and documentation requirements

The results can be used to specifically optimise design, specification and system integration. This leads, step by step, to a robust and traceable solution.