RE: New lift system idea

[tlhdoc]

 Do you remember when Penn State University students were doing a project on designing a new lift system for Fleetwood?  
 
 Here is a link on what the came up with.  I like the idea.
 
 http://www.ecsel.psu.edu/~ncs124/Project3/

[mike4947]

 tlhdoc
It need adjustablility for uneven ground at the site. As most of us all know there can be up to a foot or more difference between the crank level and the ground level depending on whether the ground is up or down in relation to the axle.

[aw738]

 tlhdoc
I doubt that the spring under the treddle would provied sufficient upward force to keep the crank in motion. You would have to get a good deal of speed with the crank to get it to carry over past the top dead center position and up past bottom dead center. An example would be as your foot goes down and the connecting rod reaches the bottom you need rotational speed to get the crank to start upward. Without it the rod would be either held in the down position, pushed back up in the wrong direction or if your lucky pushed up in the correct direction. The latter is not likely to happen. The idea might sound good but I bet it would need a lot of work to make it funtion correctly. It is my belief that the students that came up with this idea should study how the crankshaft in an internal combustion engine functions.

[birol]

 tlhdoc
University students ?  For real ? Looks like a high school project to me. They don t seem to know basics of engineering. Never heard of a dead spot ? Never considered how it would fuctcion in the real world ?
 
 Cute idea, right implementation is probably not very practical or too expensive to be of any commercial use.

[aw738]

 tlhdoc
Birol
 
 You hit the nail on the head. You said in a few sentences what I used a whole paragraph to say.

[birol]

 aw738

 

ORIGINAL:  aw738
 
 Birol
 
 You hit the nail on the head. You said in a few sentences what I used a whole paragraph to say.
 

Sorry, didn t want to steal your ideas, but I was frusturated and upset when I saw th whole thing, and could not stop myself [&:] and had to say a  few things.

[aw738]

 tlhdoc
Birol
 
 I m just glad someone else can see what I see.

[brainpause]

 tlhdoc
I saw it....just didn t know how to say it. Thanks, birol and aw738.
 
 Besides, what s wrong with the crank? For those with bad backs, they can rig a drill, as many have done here. Their foot crank doesn t solve the bed pulling problem for people with bad backs, if they were trying to make it " easier."
 
 Maybe they designed the ABS roofs.
 
 Larry

[fivegonefishing]

 tlhdoc
I remember when they were soliciting for advise, I didn t have any then but I was just thinking...if it were me, and thankfully I m not any type of engineer, I would change the whole design of the pop up, not try to make the current design easier.  Maybe incorporate that game Jacob s Ladder.  So have the beds stored upside down on top of the roof. When you would crank (or use what ever mechanical device preferred), one bed would flip up and fall (controllably) into place then the second would follow, sort of like on swinging hinges instead of sliding.  Keep cranking the the roof would rise.  That would have been my suggestion.  Good for them for trying, gotta love getting a credit for trying to build a better pop up.

[Gone-Camping]

 tlhdoc
As for the spring under the pedal, as someone mentioned it would require one heck of a spring to keep the forward momentum going. What wasn t mentioned, was that a spring strong enouch to accomplish the task would be extremely hard to push/pump, there by wearing out the poor sap that set s this up. Given a choice, I d have to stick with the current hand crank design.
 
 I agree that this looks more like a high school project than a college group! I d score them a " B-"  for effort, much lower score for the actual design!

[Garrett]

 tlhdoc
I guess I am seeing something different here.  It looks to me like that is flywheel the rod is attached to.  That and the spring should be sufficient to keep it turning.  The two difficulties that I see are getting some momentum started.  It would need a major gear reduction to keep enough speed on the the flywheel.  And the obvious fact that campsites are not level so it would need to be heght adjustable.

[angelsmom10]

 tlhdoc
I can think of better things to store in the PU than that.
 
 Maybe they just wanted to keep the kids either busy or off the streets[]

[mikewilley]

 tlhdoc
Did anyone notice that the course in question is ED&G 100H (an introductory engineering drawing class)?  This was done by students who probably haven t taken any materials, statics, dynamics or other practical engineering classes yet.  Since it is a 100 level course, they probably are fresh out of high school.
 
 Given that, I will still get up on my soap box.
 
 There is a great misconception that getting a degree in engineering will teach you how to be an engineer.  The fact is that very few engineering professors could make a living as real engineers, although many can make a tidy bit in consulting (i.e. making recommendations for which you have no responsibility to reduce to working, practical products.)
 
 Engineering school teaches you how to break down complex problems into a group of small relatively simple problems.  It also teaches you how to find the answers through research and cooperation with others.
 
 I will grant you that there are a number of areas that simply will not work in their proposed design, but it seems to me that they did a good job of demonstrating their knowledge of the fundementals of project management and task breakdown.  They simply lack the most important part of an engineering education, mentoring by someone who has been there before.
 
 My guess is that these folks may well prove to be talented engineers once they get a little properly supervised experience under their belts.  When their skills improve a little, they will see many more problems with this design than we could ever point out in this forum.
 
 When I have the priveledge of training young engineers I always tell them: " When I started at my first engineering job, I was scared to death that someone would find out I had no idea what I was doing.  As it turns, out they already knew!"
 
 In summary: getting a degree in engineering isn t the same as graduating from a trade school.  When you graduate from engineering school your " real"  training begins.  Let s give these youngsters a break (and pray that the engineers a Fleetwood are smart enough to recognize the problems with this proposed mechanism).  I also want to say cudos to Fleetwood for supporting the development of our young engineers by helping to define some real world engineering problems for them to cut their teeth on.
 
 Stepping down off soap box.
 
 cheers,
 mike willey, BSEE, Texas A&M, 1978 (whoop!)

[mike4947]

 tlhdoc

(and pray that the engineers a Fleetwood are smart enough to recognize the problems with this proposed mechanism).

 This part of Mike s post made me think (always dangerous) what if the asignment in 1995 was " Come up with a roof design other than the classic aluminum roof; that would be one piece"
 
 We could be stuck wih sewing machine treadles for the next 7 years.