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Given : (little off topic math check)
RPM=7500 (loaded)
gear ratio = 16.6 : 1
Wheel diameter 1.5 inches
What is the calculated speed in the below units of measurements?
a. inches per second
b. MPH
Robot gearbox
http://i188.photobucket.com/albums/z...f/IMG_1057.jpg
The Square Root of (Total Shaft Horsepower / Weight ) x Constant = Speed
Speed Calculator
Heres how I figuerd it. I think its right bit maybe not. this is calculated on a gear reduction of 16.6:1
pi X 1.5 gives you 4.71 inches per rev. on the wheel
at a 1:1 ratio that would give you 35325 inches per minute @ 7500 rpm
divided by the ratio of 16.6 gives you 2128 inches per minute
which equates to 35.4 inches per second
which equates to 2.01 MPH.
35.4 inches per second with a 2.02 mph speed is my answer. Billy
These are the numbers I came up with also. Just checking.Quote:
Originally Posted by Billy
I usually miss the ball park and end up swagging.
DANG...well think I'll just stick to the building and redoing instead of the designing....lol. Think I'll delete my post...thats embarrassing! :o lol
Cane Pole, thats the way I remember doing it too. I checked the numbers and thats what I came up with.....well rounding was a little different. I always use pi as 3.14159, cause I don't use a fancy calculator....just a simple one.
Isn't deleting your own embarrassing posts an abuse of your moderator powers? :D:D:D
did you see the numbers I came up with?? lol
I can do alot of stuff...but math is not one of them!! :confused:
Actually if I had the stuff laying in front of me I could figure out what I wanted to do with it or what needed to be done with it...I just use trial and error on paper...lol...instead of the easy smart way like you guys....lol.
And no...not abuse of power...just saving of face...lol...I would do it for you too!! ;)
Trying to beat my own record. The robot in the video runs 32.4 inches per second. You get disqualified if you run off the track or fail to stop for the gate. The track is 1 foot wide and the turn radius (curves) are 6 inch radius.
Accuracy counts. I hope I can stay on the track at 2 mph. Speed kills.:D
This one (video) is front wheel steer. I am trying to build an articulated front wheel steer with an articulated body. Trying to overcome the mass effect some way when maneuvering thru the turns. Ain't easy. Sure is fun.
http://i188.photobucket.com/albums/z..._tomsrobot.jpg
I'll say it again CP...if I only knew half of what's in your head.......lol
Looks really cool. Wonder if there is a way to get a mass transfer going when you turn? Turn right the center of gravity shifts right, turn left just the opposite.
Newton was right. Inertia is hard to overcome. I am size restricted. 5 inch x 10 inch x 2 pounds. No height restrictions. Wonder why?:rolleyes:Quote:
Originally Posted by AgriHawg
I not mechanical. Any input truly appreciated.
Dang Tom, that reminds me of those toys when I was a kid. Battery operated cars and tanks that followed a tube you strung out over the floor for the track. The guide was a pully wheel that rode on top of the tube. I had both the cars and the tanks. Those toys were way cool to me. You are upstaging my childhood memories with the robot that follows a mere line. Looks great!
Oh, and ot times ot is ot. Learnt that from Jethro Bodine.
Quote:
Originally Posted by Cane Pole
You would have to have the front wheel mounted on a L/R spring loaded switch that would activate L/R lowering of suspension. When the thing turns, it activates the switch that causes it to lean to the inside of the turn. Is something like this what you're looking for? I would suspect it would need some kind of fine tuning adjustment each side added to it so you could maximize the effect. If this helps, throw some more my way. I love to troubleshoot. Perhaps a mercury type switch, but it might be too wishy washy to use.
And if you have enough weight left to mess with, you could make the thing flip up on it's end like Mater made the Tractors do in the movie Cars.
I could do this maneuvering using an accelerometer and manipulating a servo, but this adds more mass .Quote:
Originally Posted by Crappie Reaper
Overcoming the effects of mass is why I am experimenting with the articulated body.
I don't have a clue as to how to distribute the weight of the articulated frame. Decisions. Decisions. haha. I don't even know what the frame will look like yet.:o But, the processor program works.;)
All inputs stimulate the thought process.
Thanx
I don't know about this. My wife says my breaths smells cause my head is full of Chit.:DQuote:
Originally Posted by rnvinc
Ment to tell everybody that the robot stops at the gate cause it got sonar.
Yep. Works just like the "fishfinder".
Oh..pshaw....you're a mess....hehe!!
I agree with the mercury switch...it would be wishy washy on a horizontal plane...just the slightest turn would make it engage...if you could some how make it variable rate though. Much like the older speed conrols in R/C cars. They used a sweep design run off a servo. As the servo swept foward the speed control hit a plate with less resistance...had a resister on it...all the way up until there wasn't any resistance.
If you could some how use a mercury swith...or a gyro...like the Segway uses to keep it vertical...but smaller. Alot like our since of balance works.
Maybe have the mercury in some sort of U shaped glass tube...it would take some of (you guys) math skills to figure out the inertia of the "said" turn...have a metal strip on the top and bottom of the glass tube....as the mercury flows to one side or the other...it contacts the metal strips to complete a circuit...as it continues to end of the U shaped glass tube...the current gets less and less resistance...giving you more and more current.
Have this hooked up to some sort of spring or servo...it would need to work much like a varible rate powertool...the more you push the trigger...the more current you get...
As you turn...sharper....faster....the mercury goes farther....as it goes farther it gives more current to the "leveling" servo....which in turn...compensates for the force of the turn. It would take alot of math to get the tube at the right angle for your speed and angle of your turn...but in my mind...logically it would work. Just something to think about. Thinking of R/C cars...the mercury switch mentioned before...the way a thermostat works on an air conditioner (before digital)...and a Segway...all that together I think it could be done.
I can see it in my mind....would just take someone telling me how to build it...lol.
Hope that all doesn't sound crazy...lol.
I got it. Lean into a curve like a motorcycle. I don't believe I have time this year to peruse this idea. I sure will investigate the possibilities.
What are some thoughts on an articulated body? The main mass of these robots are the batteries. I have articulated steering and drive. The drive motor should be physically passed the curves and heading in another direction before the batteries reach the curve. This should redirect the mass and not overshoot the curve as it would in a uni-body device.. I hope. I believe. I don't know.:o:o
I could use this accelerometer to accomplish what you all are talking about with the mercury switches.
Hitachi H48C Tri-Axis Accelerometer Module
That was my initial point I was attempting to make. I'm neither an Engineer, of a mechanical or electrical nature. But I know I can look at something, take in the info of the problem, and troubleshoot a possible solution. Keyword being "possible". A number of options should always be presented to let the customer decide. Thus, the mercury switch, which I knew would be too unstable. Good luck with the project. It sounds fun.Quote:
Originally Posted by Cane Pole
Went to Agrihawgs last night to put my XM radio in and look at his powdercoating stuff and we got to talking. The mass transfer thing he was talking about seems like it would probably work. Put the batteries low in the car...put them on some sort of slider...as you turn the mass of the batteries move to one side of the car to the other. You might could set this up with the servo for steering turning a gear that pushes the batters one way or the other on the frame.
As far as articulation...are meaning like a skidder or large tractor that is articulated in the middle?? Or do you mean a frame that would articulate and lean in curves?? You could build one that leaned by allowing it to pivot...like the front of a tractor...or the way rock cralwers work when they use a solid axle. Would be neat to try...if you could make the mass transfer and articulate the body or frame...I think the only thing that would keep you off the track would be traction from the tires. That front tired needs to lean also in my opinion...much like you steer a road grader.
Articulated like a large tractor. Don't forget, I am size and weight constrained. I like the Idea.Quote:
Originally Posted by Scrapper
Excellent link.Quote:
Originally Posted by IBNFSHN