On 04/08/14 13:18, Aplin Alexander T wrote:
Classification: UK OFFICIAL Handling Instruction: /DISCLAIMER - this is a personal e-mail and only represents only the views of the sender/ Jake Anderson:I do like the idea of the test being done in basically a clear bell jarinside a (large) Faraday cage.I also like the pendulum, however I'm less keen on the piezo pressuresensor.I suggest a laser interferometer aimed at the pendulum. If you want to verify thrust in a direction put 2 test devices on it,have the oppose each other, turn one on you should get a displacement in one direction, turn it off you should return to zero, >turn the other on displacement in the opposite direction, you don't need to make any changes inside the test device to perform the test which is nice. FWIW Jerry Pournelle (SF author and former aerospace engineer who previously encountered the ‘Dean Drive’) is also pro the ‘pendulum in vacuum’ test method:
I don't think that's enough - at the least you need two joints, one at the top and one at the bottom of the pendulum arm. Otherwise a clever fraudster could simply move the center of mass of the drive/bob to one side, and the arm would tilt.
Worse, even a two-joint arm would not be enough - a suitably oriented attitude control gyroscope could still cause the main arm to tilt.
I'm not sure even three joints is enough, though I'm not certain of that - spinning up a gyroscope might cause a tilt for long enough
-- Peter Fairbrother
http://www.jerrypournelle.com/chaosmanor/dean-drive-and-nasa/ And http://www.jerrypournelle.com/chaosmanor/dean-drive-and-many-other-matters-a-mixed-mail-bag/ ** *Alex Aplin* "This e-mail and any attachment(s) is intended for the recipient only. Its unauthorised use, disclosure, storage or copying is not permitted. Communications with Dstl are monitored and/or recorded for system efficiency and other lawful purposes, including business intelligence, business metrics and training. Any views or opinions expressed in this e-mail do not necessarily reflect Dstl policy." "If you are not the intended recipient, please remove it from your system and notify the author of the email and centralenq@xxxxxxxxxxx <mailto:centralenq@xxxxxxxxxxx>"