MicroMeteroid/Orbital Debris (MMOD) Hypervelocity Impact Testing & Piggyback Sensing Presented by: Kevin Poormon University of Dayton Research Institute 300 College Park Dayton, Ohio 45469-0116 937-229-2263 In-Space Inspection Workshop 2017 January 31-February 2, 2017, Gilruth Center 1
Outline UDRI overview Description of UDRI Hypervelocity Impact Test Laboratory Description of light-gas guns and their operation Testing environment Piggyback experiments Questions 2
UDRI Overview Established in 1956 as a division of the University of Dayton (Dayton, Ohio USA) Not-for-profit organization Focus is basic and applied research in engineering and science Emphasis on achieving technical objectives Fully supported by external sponsors Research Funding ~$110 Million (FY2015) Employ ~520 full time personnel 3
UDRI Impact Physics Laboratory Overview UDRI Impact Physics Laboratory is one of the largest private impact facilities of its type in the U.S. and has been conducting terminal ballistic research since 1965. World-Class 20,000 sq. foot indoor test facility has 12 gun ranges capable of propelling objects at velocities ranging from tens of feet per second to 33,000 ft/sec. Core competencies include: Hypervelocity impact testing and analysis Foreign Object Damage (FOD) research Light-armor design and evaluation Dynamic behavior of materials 4
Hypervelocity Impact Testing Facilities UDRI Impact Physics Laboratory has two, two-stage, light-gas guns used to launch projectiles in the range of 4900 ft/s (1.5 km/s) to 24,600 ft/s (7.5 km/s). Second-stage launch-tube bore sizes: 20mm (Range 4) and 30mm (Range 8) UDRI three-stage, light-gas gun Third-stage launch tube (7.62 mm bore) added to Range 8 Demonstrated launch of 0.25 gram package to 9.5 km/s without harming gun or deforming projectile Only facility in world that can launch projectiles with controlled properties to 10 km/s 5
Two-Stage, Light-Gas Gun Firing Cycle 6
UDRI Two-Stage, Light-Gas Guns 7
UDRI Hypervelocity Launch Capabilities Projectile sizes range from 1.5mm to 12.7mm for Range 4 (20mm launch tube) two-stage, light-gas gun. Projectile sizes range from 0.6mm to 3.18mm for Range 8 configured as a three-stage, light-gas gun. Projectiles are normally launched in a discarding sabot that is stripped away prior to impacting the target. Projectiles are typically aluminum, nylon, and steel spheres. Range 4 Two-stage gun Range 8 Three-stage gun 8
UDRI Light-Gas Gun Target Chambers Target chamber internal dimensions: Range 4 22 x 22 x 22 Range 8 34 x 34 x 28 Auxiliary chamber #1 (used with both guns) 36 x 36 x 42 (Can handle < 0.5 lb high explosive) Auxiliary chamber #2 (used with both guns) 68 x 92 x 24 Additional specialty chambers available for containing hazardous materials or testing in various atmospheric pressures Tests are performed in a near vacuum (3 torr to 50 torr) Typical test articles occupy a volume of 12 x 12 x 18 9
Range 4 Target Chamber Flash X-ray Head Instrumentation Port Windows Projectile Flight Path X-ray Film Tray X-ray Trigger Source 10
Range 8 Target Chamber Flash X-ray Heads Window Instrumentation Port Projectile Flight Path X-ray Film Tray X-ray Trigger Source 11
Auxilliary Target Chamber Target Support Frame Windows Instrumentation Port 12
Typical Target Mounting Configuration Witness Plate Wall Bumper 13
UDRI Hypervelocity Impact Instrumentation Multiple orthogonal pairs of flash x-ray stations available Sphere Cylinder Thin Disk Rod 14
UDRI Hypervelocity Impact Instrumentation Impact velocity measurement with laser/photodetector stations Residual/fragment velocity measurements via flash x-rays High-speed photography up to 500,000 pps (Phantom V1611 cameras) Multiple channels of data acquisition, up to 25Mhz sampling rate Accelerometers, strain gages, and load cells available 15
Testing Environment Tests performed in evacuated chambers (3 50 Torr) Impacts create impact flash that can persist for several hundred microseconds Target chambers clouded by dust and debris shortly after impact Hydrogen from gun expands into target chamber Hydrogen gas pressures at muzzle are on the order of 3,000 psi and greater. Blast tankage and sabot stripper reduce the direct pressures seen by the targets. Ejecta and debris/fragmentation hazards exist in target chamber. Flash radiography used to capture images of projectile produce an electromagnetic pulse than can be picked up on instrumentation. 16
Sabot Stripper - Pretest 17
Sabot Stripper Post Test 18
Tests can be expensive. Piggyback Experiments To evaluate sensor/instrumentation performance for detecting MMOD impacts, this instrumentation can be added to experiments being conducted to evaluate ballistic impact performance of MMOD shields, spacecraft structures, or thermal protection systems. Since cost of test is already paid for, only the cost for installation of sensors/instrumentation would be required. UDRI data acquisition systems can be available for use for sensor instrumentation if needed. 19
How do you Piggyback on Existing Experiments? Contact Kevin Poormon at: 937-229-2263 Kevin.Poormon@udri.udayton.edu Discuss what instrumentation is desired to be evaluated and any requirements needed from the UDRI test facility which may include: Power requirements Data acquisition requirements Sensor size limitations Sensor environmental exposure limitations We will need to get UDRI customer approval to piggyback Set up contract to cover any additional costs such as adding instrumentation shielding, adding/modifying cable porting, etc. 20
What to Expect Testing Rate 1 or 2 shots per day UDRI can provide triggering source for sensor instruments Testing environment Sensor instruments can be installed inside chamber or view test article through windows Pretest evacuation of range chambers takes approx. 30 minutes Access to target chamber after impact test is completed is approx. 15 minutes to bring test range back to atmospheric pressure and collect airborne particulates using a dust collector. Access to instrumentation outside target chamber after impact test is less than 5 minutes. 21
Questions? 22