This is my test photo page

I took this pic from the roof of the East District Energy Plant (on a tour) looking towards the Engineering Center @cuboulder. Notice the helical ridge (#strake) on the chimney to reduce structural #vibration due to the wind flow around it. #vortexshedding #resonance #gallopinggertie #takeatour
Check out the viscous fluid in the pressure gauge face... one use is to dampen out oscillations in the needle. #damping #vibration #lowpassfilter
Took apart an old record player. Check out the built-in springs that the player was sitting on to isolate it from external vibration. #vibrationisolation #springmassdamper #mechanicallowpassfilter
I continued the teardown of the record player and took apart the motor. Notice that rotor looks like some holes were drilled out manually. This is done to balance the rotor and therefore reduce vibration due to the center of mass not being at the geometric center. #eccentricmass #centroid #motor
To visualize the way a plate vibrates at some #resonance, you can pour sand on it and see where it collects. Those patterns are sections that don鈥檛 vibrate! I demonstrated this in class this week and a student suggested that he will put this #modeshape on his graduation cap! #modalanalysis #vibration #chladniplate #816Hz #naturalfrequency #systemdynamics
Just for fun, here鈥檚 another #modeshape at 1109 Hz. The shaker underneath the plate is basically a just a #speaker without the #diaphragm and the #functiongenerator is sending #sinewave into the shaker. Another pattern for graduation caps.
Idea for decorating your graduation cap!
#readyforschool with my #fourierseries socks! Thanks @3blue1brown_animations #geekforlife
Check out this really cool devise that measures rotation speeds of machines without any electronics! It鈥檚 a reed #tachometer and it has little beams that are tuned, by adding material to the ends, to a specific #naturalfrequency so that the machine鈥檚 #vibration will excite the specific #resonance . The video shows the tach laying on my engine and then revved up to 3000 #rpm and see the reed at 2900 vibrating like crazy. #springmassdamper #noelectronics #mechanicalengineering
Check out this really cool devise that measures rotation speeds of machines without any electronics! It鈥檚 a reed #tachometer and it has little beams that are tuned, by adding material to the ends, to a specific #naturalfrequency so that the machine鈥檚 #vibration will excite the specific #resonance. #springmassdamper #noelectronics #mechanicalengineering
The pitch knob adjusts the speed slightly. Notice that the still pattern starts to spin slowly when your speed is off for 33 rpm and your LongPlay record won't sound quite right. #LP #audiotech #strobedisc Mar 4, 2017, 9:21 AM At 33 rpm the outer disc looks still and at 45 rpm the inner disc looks still. #aliasing #signalprocessing Mar 3, 2017, 6:43 PM These patterns, printed on paper, are used to tune/verify the speed of turntables for either 33.3 or 45 rpm. See accompanying video to see it in action. #str
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I鈥檓 on a thesis committee for #phd candidate who is doing advanced #control of an #atomicforcemicroscope which will take 鈥渋mages鈥� of materials zoomed in further than what optical microscopes can do. You can imagine that vibration, at such zoomed-in levels, would cause the image to become blurred. See the #vibrationisolation table that he built by hand out of wood and bungee cords! This will reduce the vibration passing from ground into the #afm . Check out those #pocketholes #woodworking #diy #frequencyresp