Second Environment Sensor For Tube Launched …...Second Environment Sensor For Tube Launched...
Transcript of Second Environment Sensor For Tube Launched …...Second Environment Sensor For Tube Launched...
Second Environment SensorFor Tube Launched Non-Spun
MunitionsApril 9, 2003
TTank-automotive & AArmaments COMCOMmand
LeadershipTeaming
CommunicationEmployee SupportStrategic ThinkingOrganizational Climate
Providing AmericaAdvanced Armaments
for Peace and War
John I. NickelElectronics Engineer, Fuze Division
47th Annual NDIA Fuze Conference
4/9/2003 JIN / DWW 2
Committed to Excellence
Participants
Curt Anstine, Mechanical Engineer Jim Campbell, Mechanical Engineer
Julian Knisley, Mechanical TechnicianJohn Nickel, Electrical Engineer
Dennis Ward, Team Leader Ron Wardell, Senior Electrical Engineer
4/9/2003 JIN / DWW 3
Committed to Excellence
Smooth vs. Rifled BoreLaunch Environment Sensing
• First environment indicator
– Setback is a robust first environment for both artilleryand mortar rounds
• Second environment indicator
– Artillery rounds typically employ spin to sense launchenvironment and to activate reserve power sources
– Spin cannot be used for smoothbore mortars andother non-spun munitions
– Mortars often use air-driven turbines to sense air flowas a second environment and to generate power
4/9/2003 JIN / DWW 4
Committed to Excellence
Alternative 2nd Environment Sensor
• Mortar and other non-spun munitions could employan electrically-sensed muzzle exit signature for asecond environment indicator
• A sealed electronic sensor would not haveenvironmental exposure concerns as turbines do
• Goal of sensor is to determine a unique tubesignature that clearly indicates a launch environment
4/9/2003 JIN / DWW 5
Committed to Excellence
• RF-based 2nd environment sensor
– Active sensor that transmits RF energy, whichpropagates in mortar tube as though in a circularwaveguide
– Some RF energy is reflected back from theimpedance mismatch between mortar tube muzzleand free space
– Sensor output at any moment is the instantaneoussum of transmitted and reflected waves at that pointin the tube
– Sensor output contains velocity information
2ND Environment SensorOverview
4/9/2003 JIN / DWW 6
Committed to Excellence
Sensor Development Activities
• Defined sensor architecture
• Collected data in lab on mock-ups of 60mm, 81mm, and120mm mortar tubes. Data included time-zero, sensoroutput, and tube exit indication
• Collected time-zero and sensor data under ballisticconditions on 60mm, 81mm, and 120mm mortars at APG.Data was collected using on-board recorders
• Analysis of collected data and work on sensing andprocessing algorithm development
4/9/2003 JIN / DWW 7
Committed to Excellence
Sensor Architecture
4/9/2003 JIN / DWW 8
Committed to Excellence
Typical Lab Test Set-up
60mm mock-up tube
Lab test vehicle
RF absorbent tominimize reflections
4/9/2003 JIN / DWW 9
Committed to Excellence
Signature of MicrowaveTransmitter in a 60mm Tube
T-ZeroExit
Sensor Output
Expanded Trace
4/9/2003 JIN / DWW 10
Committed to Excellence
Signature of MicrowaveTransmitter in a 81mm Tube
Exit
Sensor Output
Expanded Trace
T-Zero
4/9/2003 JIN / DWW 11
Committed to Excellence
Signature of MicrowaveTransmitter in a 120mm Tube
Exit
Sensor Output
Expanded Trace
T-Zero
4/9/2003 JIN / DWW 12
Committed to Excellence
BallisticTest #1
BallisticTest #2
RF Sensor Test Matrix
3221
1112
1113
3224
3234
3231
QtyQtyQtyCharge
120mm81mm60mm
4/9/2003 JIN / DWW 13
Committed to Excellence
81mm test circuitboard and vehicle
60 / 120mm test circuitboard and vehicle
Ballistic Test Hardware
4/9/2003 JIN / DWW 14
Committed to Excellence
Ballistic Test Hardware During Assembly
Test Vehicle Parts Pre-assembly testing
Potted sensor Battery Data recorder Connector cup
4/9/2003 JIN / DWW 15
Committed to Excellence
Ballistic Test Results
Field test results were drastically different from labresults!
• Setback, balloting and other shocks induced high noiselevels into the circuitry
• Potting compound degraded IF signal
• Outward flaring of mortar tube lip reduced the amountof energy reflected back, thus lessening the sensitivityand effectiveness of the sensor
4/9/2003 JIN / DWW 16
Committed to Excellence
Test Results - Raw Sensor Data
Sensor outputcontains velocityinformation
81mm Chg.1 (Lowervelocity)
81mm Chg.4 (Highervelocity)
4/9/2003 JIN / DWW 17
Committed to Excellence
Test Results - Raw Sensor Data
Sensor outputcontains weaponinformation
120mm barrel (69.1”)
60mm barrel(35.3”)
4/9/2003 JIN / DWW 18
Committed to Excellence
Test results - Raw Sensor Data
Induced noise candrastically increasewith firing charge
120mm, chg 1
120mm, chg 4
4/9/2003 JIN / DWW 19
Committed to Excellence
2nd Environment SensorTask Summary
Completed:
• In-lab tube characterization tests (60, 81, 120mm)
• Ballistic environment tube measurements conductedin 60, 81, and 120mm mortar tubes at all chargeconditions and ambient temperature
• Sensor data reduction and analysis conducted
4/9/2003 JIN / DWW 20
Committed to Excellence
Conclusions
Overall, the sensor shows promise, but it needs work
• Further investigation of waveguide propagationphenomena
• Refinement of detection and processing algorithm
• Redesign of RF and IF circuitry to minimize noise,temperature effects, unexpected interactions and energylosses
• Blast shield for 81mm and vehicle-mounted 120mmmortars should be included in testing