Design Con 2015
Breaking News
Comments
Newest First | Oldest First | Threaded View
Page 1 / 2   >   >>
JamesBurt
User Rank
Rookie
Absolutely dumbfounding
JamesBurt   3/13/2014 3:39:20 PM
NO RATINGS
This video is absolutely dumbfounding to me.  

For some reason this video is posted all over the internet, in some places with a 10 minute introduction where the "experimenters" spew forth all their supposed "credentials".

 

In the end, they simply proved that yes, you can plug an ac adaptor into a battery powered device, and the ac adaptor will last longer than the battery.  What an EARTH SHATTERING revelation!

 

Amazingly, all their "credentials" failed to help them realize what an 8th grade hobbyist realizes.... a device with a larger battery needs a larger ac adaptor....and that there is current loss through cables (head plant!).  I half-expect them to try to start their automobile with a 9v transistor battery next!

 

Then, they went on to proudly display their "achievements" (and lack of basic knowledge) by posting this all over the internet...  LoL.

 

WKetel
User Rank
Rookie
How to make it work the first time, or close to the first time.
WKetel   9/24/2013 4:53:11 PM
NO RATINGS
In odreder to make it fly with remote power you need to have the cable light enough so that it can be lifted, and you also need to be able to supply enough voltage at the required currentm draw. So you must find out the current draw at the required voltage. And you must determine the amount of lifting force available. If the cable is going to be so small that it has a big amount of voltage drop, then the power supply must deliver enough voltage to compensate for that voltage drop, and it must have enough currnt capacity to supply the needed voltage while delivering that current. Besides that, the weight of the selected cable must be less than the available lifting force.

Calculating or measuring these three things will allow a reasonable chance of a first-time success. Starting to try without knowing those three things is just an excercise in wasting time and effort. You might possibly be lucky and find something that works, but probably not. Which your first few attempts showed.

Robotics Developer
User Rank
Rookie
Re: IR Drop
Robotics Developer   9/20/2013 8:38:18 PM
NO RATINGS
I would say that a week is not enough time to do much and they at least got something accomplished.  If I were to revisit that effort I would have suggested building a larger quad-copter with greater lift and larger battery options.  The tether is a great starter for debug but not a real long term solution, the full benefits of a copter can only be realized un-tethered.

Robotics Developer
User Rank
Rookie
Re: IR Drop
Robotics Developer   9/20/2013 8:37:32 PM
NO RATINGS
I would say that a week is not enough time to do much and they at least got something accomplished.  If I were to revisit that effort I would have suggested building a larger quad-copter with greater lift and larger battery options.  The tether is a great starter for debug but not a real long term solution, the full benefits of a copter can only be realized un-tethered.

Caleb Kraft
User Rank
Blogger
Re: IR Drop
Caleb Kraft   9/20/2013 8:50:45 AM
NO RATINGS
that's a pretty good idea!

Caleb Kraft
User Rank
Blogger
Re: IR Drop
Caleb Kraft   9/20/2013 8:49:56 AM
NO RATINGS
that's a pretty good idea!

Caleb Kraft
User Rank
Blogger
Re: IR Drop
Caleb Kraft   9/20/2013 8:47:17 AM
NO RATINGS
yeah, one week is hardly enough time to recognize the issue and come up with a prototype, much less refine it.

HeyJoe0
User Rank
Rookie
Re: IR Drop
HeyJoe0   9/19/2013 11:01:46 PM
NO RATINGS
I agree with running a local regulator and feeding higher voltage. You could also run much thinner wire and the flight dynamics will respond closer to the final untethered version. 

Robotics Developer
User Rank
Rookie
Re: IR Drop
Robotics Developer   9/19/2013 9:33:25 PM
NO RATINGS
Another option would have been to supply a higher than needed voltage and provide on board voltage regulation.  This would avoid the 4 wire remote sensing and still enable full votage/current at the copter.

ShawnHymel
User Rank
Rookie
Re: IR Drop
ShawnHymel   9/19/2013 8:29:12 PM
NO RATINGS
We actually discussed having a supply change its voltage to accommodate the large drop depending on the current. While it should work, Tara and Sean had limited time during their hacker-in-residence stay.

Page 1 / 2   >   >>


Flash Poll
Top Comments of the Week
Like Us on Facebook
EE Times on Twitter
EE Times Twitter Feed

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
Max Maxfield

Analog Faceplate Design Decisions: Art or Science?
Max Maxfield
1 Comment
My degree is in Control Engineering -- a core of math with "surrounding subjects" of electronics, mechanics, and hydraulics and fluidics. The only official programming I did as part of ...

Jolt Judges and Andrew Binstock

Jolt Awards: The Best Books
Jolt Judges and Andrew Binstock
1 Comment
As we do every year, Dr. Dobb's recognizes the best books of the last 12 months via the Jolt Awards -- our cycle of product awards given out every two months in each of six categories. No ...

Engineering Investigations

Air Conditioner Falls From Window, Still Works
Engineering Investigations
3 comments
It's autumn in New England. The leaves are turning to red, orange, and gold, my roses are in their second bloom, and it's time to remove the air conditioner from the window. On September ...

David Blaza

The Other Tesla
David Blaza
5 comments
I find myself going to Kickstarter and Indiegogo on a regular basis these days because they have become real innovation marketplaces. As far as I'm concerned, this is where a lot of cool ...