Open Research Topics

Topic 1: Investigation into the dynamics and control of CLGP/M with HILS

 

Supervisors: Milan Beharie (CSIR), Prof Laurent Dala

1.    Background

Conventional artillery has proven to be effective against stationary targets where precise delivery is not required however this may not be the case for moving targets and hard point targets(tanks-small areas of vulnerability), where the artillery fire needs continuous adjustment. With the advance of embedded hardware technology MEMS based inertial navigation, closed loop GNC is possible..  Projectiles like the Copperhead are guided to a target by semi active laser and are capable of defeating armour and targets at ranges over 6 kilometres. This class of ammunition is guided using aerodynamic control mechanisms such as spin and fin stabilisation. Both concepts use canards, located on the forward part of the weapon for guidance, but differ on the method chosen in order to provide the airframe with dynamic stability. Fin-stabilized projectiles use aerodynamic surfaces located at their aft section whereas spin-stabilized maintain a high airframe spin rate which guarantees gyroscopic dynamic stability. Even though the latter are simpler to implement, since they use the initial spin rate of the ballistic weapon, the canard actuators need to be of extremely high bandwidth since they must modulate the control signal to this high frequency. One of the solutions to this inconvenience is the so-called dual-spin course correction fuse concept which uses a co-axial motor to decouple the projectile body from the guidance fuse, also containing the software and hardware needed for guidance. The aim of this project will include the development of the dynamics and control of a projectile similar to the copperhead with a full conception of a hardware in the loop simulation. 

 

Figure 1: M712 Copperhead cannon launched 155 Calibre


 

Topic 2: 155 Calibre Canon Launched UAV

Supervisors: Milan Beharie (CSIR), Prof Laurent Dala

1.    Background

The problem with majority of UAV’s is the slow deployment time. This drone is launched inside a specially designed warhead inside a rocket or artillery shell. Artillery launch provides the drone with speed and mobility advantages over small hand launched UAVs like the Raven. At the appropriate attitude, the warhead deploys a parachute in order to slow down and release the drone. The drone then uses its four wings to stay aloft, while it scans for enemy vehicles. An operator back at the artillery battery designates the drone to use its laser (as well as any another sensors) to lock onto enemy vehicles by marking their rooftops, just like the laser designator on a Reaper drone or Apache attack helicopter. Top down attacks on enemy vehicles by artillery guided by the drone's laser are effective as they allow attacked on the vulnerable areas of the tanks. This study will requires a complete evaluation of the mission profile, vehicle dynamics, control and hardware specifications.

1.1            Requirements

  1. The UAV shall be delivered to target area in a 155 mm artillery shell. [UN.1]
  2. The UAV shall have an optical payload in the 0.5 - 1.0 kg class. [UN.2]
  3. The UAV shall loiter in the target area for 10 - 30 minutes. [UN.3]

1.2            Assumptions

  1. Fired from 155 mm self-propelled howitzer.
  2. Minimum acceleration during firing: 20,000g.The UAV will be transported to the target area in an unguided artillery shell with the outer dimensions and mass properties typical of shells fired by 155 mm artillery pieces.  In the absence of further information, the data from Ref. [1] is used as a starting point below.
  3. Wind velocities in the target area are low enough and predictable to allow a reasonable dwell time.

Figure 1: Geometry of reference 155mm projectile (Ref. [1])

 

Table 1: Mass properties of reference projectile

Mass

m

43.7 kg

Centre of mass relative to nose (Figure 1)

xCG

0.563 m

Moments of inertia of projectile (relative to CG)

 

0.1444 kg.m2

 

1.7323 kgm2

 

1.7323 kg.m2

 

1.1.1        Derived and assumed requirements

1.1.1.1          Functional requirements

  1. The UAV shall have an optical payload. [R.1]
  2. The UAV shall loiter in the target area (fully functional) for at least 10 minutes. [R.2]
  3. The UAV system shall transmit the captured imagery continuously to an operator located at the artillery battery or vehicle. [R.3]
  4. The imagery presented to the operator shall be stabilised. [R.4]
  5. The operator shall be able to “zoom” into any area of interest within the imaged area. [R.5]
  6. The system shall be able to “lock-on” to and automatically track any object designated by the operator. [R.6]
  7. The UAV system shall be able to continuously determine the coordinates of any object identified in the captured imagery. [R.7]
  8. The UAV shall be delivered to the target area in a 155 mm artillery shell. [R.8]
  9. The UAV system shall use the environmental and targeting data available to the artillery system to compute the firing aim point and deployment profile that maximises its performance in the target area. [R.9]
  10. The UAV itself may be disposable after use. [R.10]
  11. The UAV shall shut down and cease transmissions either when commanded to do so or when it is no longer able to function as required (e.g. when its altitude is too low). [R.11]
  12. If or when the UAV is no longer able to perform its mission, it shall be disabled in such a way that anybody finding it will not be able to operate or reuse it. [R.26]
  13. The UAV shall be returned to the ground in a manner that minimises damage to entities on the ground as soon as its mission ends. [R.30]
  14. Multiple UAV shall be used simultaneously without interfering with each other. [R.23]
  15. An operator shall only operate one UAV at a time. [R.24]
  16. The UAV system shall maintain reliable communications between the operator and the UAV despite the present of adversary jamming, spoofing and other sources of electromagnetic interference. [R.28]

1.1.1.2          Performance requirements

  1. The UAV shall be deployed to target areas at least 30 km from its firing unit. [R.12]
  2. It shall be possible to recognise the type of vehicle in the imagery. [R.13]
  3. It shall be possible to recognise people moving in a cluttered environment and determine what they are doing (e.g. discriminate between refugees fleeing from a team setting up a mortar). [R.14]
  4. The optical sensor shall operate in daylight and if possible have limited light capabilities. [R.15]
  5. The UAV shall image and locate targets in an area of 500 m radius beneath itself. [R.16]
  6. The imagery presented to the operator shall be stabilised to TBD. [R.17]
  7. The CEP of target coordinates generated by the UAV system shall be within 10 m radius. [R.29]
  8. The UAV shall be sufficiently rugged to withstand the blast from artillery shells landing in the target area beneath it without compromising its performance. [R.18]
  9. The UAV system shall be stored for up to 10 years without requiring maintenance. [R.25]

1.1.1.3          Constraint requirements

  1. The UAV system shall integrate with existing artillery vehicles and personnel.  No additional vehicles or staff should be necessary to operate the system. [R.19]
  2. The UAV system shall incorporate an operator station that is usable inside an artillery vehicle. [R.20]
  3. The UAV system shall be usable by artillery unit personnel with minimal additional training. [R.21]
  4. When the UAV is operating, it should not be visible to the naked eye by an observer on the ground. [R.22]

 

- Author Dala
Published by Barbara Huyssen

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