HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
REGISTER   |   LOGIN   |   HELP
<<  <  Page 2/4  >  >>
armorris
User Rank
Platinum
What about magnetic damping?
armorris   7/25/2013 8:52:13 AM
NO RATINGS
Jason Brack,

What about magnetic damping, where a strong magnet moves through a coil of wire? A shorted coil would be solidly damped, like a shorted generator. You would change the damping factor by varying the resistance across the coil. You could use a bridge rectifier and a MOSFET as the variable resistor. Better yet, two series connected MOSFETs with their gates and sources tied together. It would take almost no power to control the damping factor. You could run the controller for a long time on a 9 volt battery.

tkhorton
User Rank
Silver
Curious
tkhorton   7/25/2013 8:48:45 AM
NO RATINGS
Just curious. What are the majors of the students who participated? Also, how did the idea for this project come about? What was the deciding factor in picking the Arduino board versus maybe a Beagleboard?

Elizabeth M
User Rank
Blogger
Re: Cell phone would be better
Elizabeth M   7/25/2013 6:49:04 AM
NO RATINGS
I agree that this is cool, naperlou, but the screen placement is worrisome for me, too. And maybe it's a little too cumbersome for biking? But it's great to see such forward thinking and innovation.

Nancy Golden
User Rank
Platinum
Great Job!
Nancy Golden   7/23/2013 5:32:33 PM
NO RATINGS
Keeping in mind that the temptation for students is to overreach what they are able to do in the course of a class because of all of the options that are available - I think they did a fantastic job and they kept the project achievable. While I agree that the placement perhaps needs to be redesigned, I view this as I would a working prototype and no doubt the students involved learned a lot about multiple disciplines during the course of their work. Bringing a project from design to completion is no small task and I applaud their efforts.

mrdon
User Rank
Gold
Re: Cell phone would be better
mrdon   7/23/2013 5:14:01 PM
NO RATINGS
Tool_maker Thanks for the insightful example. I have experienced similar situations with students as well and for whatever reason, the light bulb turns on when least expected. 

Tool_maker
User Rank
Platinum
Re: Cell phone would be better
Tool_maker   7/23/2013 3:35:23 PM
NO RATINGS
Unfortunately, that was my point. You will have a plethora of students who want to make the video, but very few who will want to work on the bike. However, as you state letting the students take ownership yields much more positive results.

When I was still teaching and I assigned a research paper, I never received near the quality as when it became an I-search paper for which the student could choose their own topic, do first-hand interviews and experiments and report their findings and failures. (That was hard to convince students that what did not work can sometimes be as valuable as what did work.) One of the best papers I got came from a very hard to motivate student who wrote an excellent paper, complete with illustrations, on the evolution of hockey sticks. He wrote a ton of letters, received enough responses from players from different eras that he gained sufficient knowledge to produce a quality paper.

What was really cool was that I seldom had to direct the students to get back on task as each was anxious to get to work on their project.

mrdon
User Rank
Gold
Re: Cell phone would be better
mrdon   7/23/2013 2:09:49 PM
NO RATINGS
Tool_maker Thanks for the confirmation. Your correct about how social media has an impact on educational endeavors. Maybe the key to increasing active educational participation is to allow total student ownership of the video production. In addition to creating the product and engineering documentation, the students will be involved in the planning of the video recording/production. Hopefully, this hands-on involvement will promote active participation among the students. Hopefully!!!

Tool_maker
User Rank
Platinum
Re: Cell phone would be better
Tool_maker   7/23/2013 12:55:12 PM
NO RATINGS
mrdon: I completely agree about getting caught in the glitz etc. and no substitute for hands-on-experience. I would bet a majority of students would be more interested in producing a Zoom -Pow video with exploding bikes and a rock soundtrack rather than this straight forward: Here it is approach. Many would volunteer for the video, few will be willing to give up time for the bike. Just look at some of the elaborate pranks and tricks on various social media web sites.

GopherT
User Rank
Silver
Wrong iron powder
GopherT   7/23/2013 11:04:53 AM
NO RATINGS
Guys, the correct iron powder for MR systems is spherical and under 15 microns (even better under 7 microns). Two companies, BASF and Ashland make iron powder from a chemical process that meets these specs (these two companies also sell powder that is already annealed). It has excellent magnetic properties if the carbon is reduced (removed) by an annealing process. The spherical shape allows even a rare earth magnet to activate a shock. The MR shocks use nothing close to 10 amps. The small iron powder flows through very small orifices so the switching does not have to be great magnetic flux if your path is small. Previous poster said it well, this is a combination of mechE, EE and chemistry among others. Now, finding the right software control logic is your next big task!

mrdon
User Rank
Gold
Re: Nice blend of sciences
mrdon   7/22/2013 8:43:42 PM
NO RATINGS
Rob, Another reason for my students to submit their projects to the magazine. Gadget Freak provides hands-on, real world experience for the students base on their submitted designs to the magazine. Yes, it does provide a nice item to include on their resumes.

<<  <  Page 2/4  >  >>


Partner Zone
Latest Analysis
A new web-based software tool aims to give engineers a fast, intuitive way to design circuit-protection systems for their electronic products.
The National Highway Traffic Safety Administrationís recent backup camera mandate could open the door to more vehicle innovations, including better graphical displays, 360-degree camera views, and the increased use of Ethernet.
With support from National Instruments, a group of dedicated students from Connally High School in Austin, where more than 50% of the students are at risk of not graduating, have created a successful robotics team that is competing in the FIRST World Championships.
Solar Impulse 2 -- a 100% solar-powered airplane -- has been completed. It features several advanced materials, some developed specifically for next year's attempted around-the-world flight.
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
More:Blogs|News
Design News Webinar Series
3/27/2014 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
2/27/2014 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
12/18/2013 Available On Demand
11/20/2013 Available On Demand
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Apr 21 - 25, Creating & Testing Your First RTOS Application Using MQX
SEMESTERS: 1  |  2  |  3  |  4  |  5


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: April 29 - Day 1
Sponsored by maxon precision motors
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service