1. Experimental Study of the Machian Mass Fluctuation Effect Using a µN Thrust Balance N. Buldrini, K. Marhold, B. Seifert and M. Tajmar Space Propulsion – ARC Seibersdorf Research nembo.buldrini@arcs.ac.at

2. Machian Mass Fluctuations 1 2 Impulse Term Exotic Mass Generator term Always negative!

3. Machian Mass Fluctuations ≈ Mass Fluctuation in a Capacitor Capacitor Volume Delivered Power

4. Ballast Mass Fluctuating Mass Mass Fluctuations for Propulsion What if you can make the mass of a capacitor fluctuating and act on it in a direction when it is heavier and in the opposite direction when it is lighter?

5. ~ Actuator (piezoelectric material) Capacitor Ballast Mass Power Supply Thrust Machian Mass Fluctuations The Devices

6. ~ Capacitor ~ Power Supply Coil The “Flux Capacitor” Machian Mass Fluctuations The Devices Magnetic Field Force Electric Field

7. B E F Machian Mass Fluctuations The Devices

8. The Tested Devices Mach-5C Mach-5C Claimed Thrust: ~ 30 μN Mach-6C Mach-6C Claimed Thrust: 100-200 μN B E ThrustDirection Capacitors are under the coil

9. The Tested Devices

10. The Experimental Setup Vacuum Chamber used for testing Material: Stainless Steel Vacuum: 10 -6 mbar Vacuum Chamber and Thrust Balance Thrust Balance arrangement inside the Chamber. Balance succesfully tested with In-FEEP thrusters! Device Sensor Assmbly Pivot

11. The Experimental Setup Device Arrangement on the Balance

12. The Experimental Setup Thrust Balance Device Mounted on the Balance

13. The Experimental Setup Thrust Balance Thrust Balance Pivot and Device Feeding Cables C-Flex G-10 Flexural Pivots

14. The Experimental Setup Thrust Balance Optic Sensor and Damping Actuator Assemblies Optic Sensor Detail

15. The Experimental Setup Thrust Balance Principle: Measures the reflection of light Principle: Measures the reflection of light Only fiber optic parts in the vacuum chamber (no EMI) Only fiber optic parts in the vacuum chamber (no EMI) Noise: 0.008 µm (DC-100Hz) Noise: 0.008 µm (DC-100Hz) Philtec D64 Fiber Optic Displacement Sensor

16. The Experimental Setup Device Wiring Schematics Same setup used by Woodward and March. Amplifiers from March and original step-up transfomers from Woodward.

17. Experimental Results Mach-5C This kind of behaviour indicates the presence of thermal effects on the feeding wires

18. Experimental Results Mach-5C ~ Predicted thrust at 90° phase shift between capacitor voltage and coil current: ~ 5µN Zero thrust predicted at 180° phase shift Thermal drift is still present.

19. Experimental Results Mach-6C The thermal drift has been reduced re-arranging the wiring and reducing the firing time to 2 seconds Cap.voltage: 3.2 kVp Coil Field: 250 Gauss Frequency: 52 kHz Cap.V / Coil I - Phase Relationship: 90deg Expect. Thrust: ~150µN - Capacitor Power - Coil Power - Thrust Trace

20. Experimental Results Mach-6C 50µN Pulse Superimposed A pulse of 50µN was generated during the firing time by the calibration actuator, to test the response of the balance - Capacitor Power - Coil Power - Thrust Trace Cap.voltage: 2.5 kVp Coil Field: 200 Gauss Frequency: 55 kHz Cap.V / Coil I - Phase Relationship: 270deg Expect. Thrust: ~50µN

21. Experimental Results Balance Response to Short Pulses A series of short pulses was generated using the calibration actuator, to evaluate the balance response at different thrust/pulse duration values

22. Experimental Results Mach-6C Mach-6C was sent back to Woodward to be tested again Tests in air by Woodward showed a thrust effect possibily due to an electromagnetic interaction. The device has been then potted, and tested in vacuum. A residual thrust of 100-200µN was recorded Then the device was sent back again to ARC-sr

23. Experimental Results Mach-6C Potted The phase relationship is changing during firing time, expecially at high capacitor power levels. Two calibration pulses of 50µN were generated with duration of 0.8 and 0.5 seconds to test the response of the balance in case of shorter thrust events Cap.voltage: 3 kVp Coil Field: 200 Gauss Frequency: 52 kHz Cap.V / Coil I - Phase Relationship: 270deg Expect. Thrust: ~75µN

24. Experimental Results Mach-6C Potted Capacitor + Coil Energized together Only Capacitor Energized

25. Experimental Results Mach-6C Potted Only Capacitor Energized Only Capacitor Energized (Shielded Cable)

26. Experimental Results Test at Higher Frequency / Different Dielectric Expected Thurst: 1 ÷ 6 mN No thrust was detected within the sensibility of the used electronic balance (0.1mN) Dielectric: Titanium Oxide Series Tank Circuit Self-contained Device Voltage: 2.3 kVp Frequency: 2 MHz Dielectric: Titanium Oxide Series Tank Circuit Self-contained Device Voltage: 2.3 kVp Frequency: 2 MHz

27. Conclusions and recommendations Mach thrusters, tested by Woodward, were characterized using highly sensitive µN thrust balance used for electric propulsion Mach thrusters, tested by Woodward, were characterized using highly sensitive µN thrust balance used for electric propulsion Our measurements rule out a thrust above 50% of the theoretical predictions and previous claims. It is likely, that this threshold is even reduced to 10% as indicated by part of our data. Our measurements rule out a thrust above 50% of the theoretical predictions and previous claims. It is likely, that this threshold is even reduced to 10% as indicated by part of our data. A device operating at higher frequencies and with different dielectric was designed and built at ARC-sr. No thrust of the magnitude predicted by the models developed by Woodward/March/Palfreyman was observed A device operating at higher frequencies and with different dielectric was designed and built at ARC-sr. No thrust of the magnitude predicted by the models developed by Woodward/March/Palfreyman was observed An upgrade of the sensor setup presently used by Woodward/March to a torsion balance or a ballistic pendulum setup is recommended An upgrade of the sensor setup presently used by Woodward/March to a torsion balance or a ballistic pendulum setup is recommended Due to the difficulties in keeping the right phase relationship between E and B fields, and thus same operating conditions, the development of a device based on a tank design is recommended Due to the difficulties in keeping the right phase relationship between E and B fields, and thus same operating conditions, the development of a device based on a tank design is recommended The development of a self-contained device similar to the one built at ARC-sr is proposed as well, using barium titanate as dielectric The development of a self-contained device similar to the one built at ARC-sr is proposed as well, using barium titanate as dielectric