Very cool Rich! I'm a fan of soda straws. McDonald's are among the best. Walmart sells a bag of large diameter strong stiff straws, I have amassed quite a collection.
Next I want to make a wiggle-drive robot based on the kid's ride-on shown. Incredible handling by the kids shown (youngest is 1.5 years old!). A great way to get drive & steering from one oscillating servo, although high speed and coasting will make it very difficult on dead reckoning...
Well, using a few tricks I pcked up from lego, can use a traveling worm gear, reverse direction and it engages a different set of gears, using a differential, you could potentially alternate which wheel gets locked just by reversing direction, assuming this is a continuous rotation servo, seeing if I can find some pictures of it in action, but you're just making a transmission, where the drive gear is free to slide along its axle, with it being a worm gear, if you reverse direction it will slide along until it can no longer slide, and then it will start rotating the gear its engaged to.
No electronics, just fabulous complicated all-mechanical action. Walks spastically, falls down, gets up, keeps going. I posted previously about these, I paid $35 or 40 for one a few years back, and I just ordered one of these knockoffs too.
If you boys don't grab one of those at $8.49 shipped, don't even talk to me anymore! Belongs on the shelf of every self-respecting roboticist. I even sent one to my brother, who ain't a roboticist and more importantly, certainly ain't self-respecting.
My project has under went a design change. In keeping with the K.I.S.S principal I went with a rear wheel braking system using Flexinol muscle wires. Steering involved to many parts and complications. I should have a working model later tonight or tomorrow
I do need to figure out how to post a video. Need to change from MPG4 to a file the site uploader will accept.
I am going to have to perfect the method of crimping the Muscle Wires. I have broke three of them so far, and running out if wire.
Also running out of time as we are leaving soon to a warmer climate for a few weeks. No computers, cell phone or Snow ! Been 20 degrees below the normal of 40 plus 15"+ of snow laying about.
I am going to have to perfect the method of crimping the Muscle Wires. I have broke three of them so far, and running out if wire.
Yes, the mechanicals of Muscle wire & nitinol are a bear and IMO why it's not used much. I had a Spacewings butterfly years back that required constant maintenance and I still have a Stiquito walking robot book/kit that's never been built. Looks great on my bookshelf though.
W9GFO Technically you are correct. Thanks for bringing this point out. Although the challenge was one motor or servo.
No matter how this all turns out. It has been an educational and interesting trip. I will be returning from vacation at the end of the month. Hope to see some more entries when I return.
Thanks to all for your support.
W9GFO Technically you are correct... Although the challenge was one motor or servo.
You could make that argument, but all the discussion has been based upon one "thing" that is actuated. If I were to use multiple solenoids to drive a robot it would not meet the spirit of this challenge even though the number of solenoids allowed was not mentioned. Besides, muscle wire meets the definition of "motor".
Motor: a machine, especially one powered by electricity or internal combustion, that supplies motive power for a vehicle or for some other device with moving parts.
At any rate, I like what you have done and hope to see more from you.
And conversely motors and servos are actuators. On that note I will respectfully withdraw my entry.
When we return from vacation I will post this project in more detail on the Projects forum.
Don, that's an awesome bot. Don't you dare withdraw your entry here. I'm grandfathering you in for creative interpretation of the rules. Besides, no one else has entered!
Great job calibrating those turns, impressively consistent 180 degree turns. No one else has used Nitinol, the thermal lag poses its own problems. Well done!
Thanks erco. My entry stands:)
I would have surely thought the the "Brain Trust" would have made an entry by now. That is those of you that work with Stamps and code full time. This is a winter hobby for me, along with my model railroad. Spring Summer and Fall it is farming and antique tractors. I will be off grid so to speak for the next few weeks. My be able to check in from time to time? We are leaving snowy North Central Ohio this morning for Eastern Tenn. See you when we return:)
OT, but this has one-servo potential and it's my thread anyway.
The moving mouth on the robot at in the video below at 0:44 caught my eye. It appears to be a rubber band moved by 4 interlocked gears and gives a really nice motion. That could be moved by a single servo, or motor, or even a solenoid for faster response. About as simple as mechanisms get.
Note that it would work MUCH better using a Parallax controller, which would imbue it with near AI-capability.
I thought this walker-roller was interesting. Simple straight-line walking mechanism has a motor/wheel on one foot for turning. So two motors, not one, but I like the thinking here. Just watch the first 20 seconds. By then, you'll be mesmerized by the soft vibey jazz.
Comments
The vehicle wheel geometry is very important. A slightly different take is this Ziggle, with 4 inclined casters: http://www.toysrus.com/product/index.jsp?productId=30875786&prodFindSrc=search&cp=
https://www.youtube.com/watch?v=5kzI_rp_1uk
http://masoncorporation.com/shop/roller-racer-amusement/
http://en.wikipedia.org/wiki/Roller_racer
I know they are good because I used to assemble them on the weekend. Must have made 3 or 4 hundred.
Not necessarily a one-servo vehicle.
Found a link kind of showing what I mean.
http://www.last-outpost.com/~malakai/lego/twospeed/index.html
No electronics, just fabulous complicated all-mechanical action. Walks spastically, falls down, gets up, keeps going. I posted previously about these, I paid $35 or 40 for one a few years back, and I just ordered one of these knockoffs too.
Jump to 0:30
Hey, my neighbor swore he deleted that video of me!!
Gakken comes up with some very interesting and entertaining things!
I do need to figure out how to post a video. Need to change from MPG4 to a file the site uploader will accept.
Youtube is pretty good at accepting a variety of formats, including MP4.
Now tell us more about your gas guzzler which only gets 4 MPG.
Certainly not with a defeatist attitude like that, Mr. Tool Chain!
How about a pic?
Also running out of time as we are leaving soon to a warmer climate for a few weeks. No computers, cell phone or Snow ! Been 20 degrees below the normal of 40 plus 15"+ of snow laying about.
Yes, the mechanicals of Muscle wire & nitinol are a bear and IMO why it's not used much. I had a Spacewings butterfly years back that required constant maintenance and I still have a Stiquito walking robot book/kit that's never been built. Looks great on my bookshelf though.
https://www.youtube.com/watch?v=JS0t4ucqlls
https://www.youtube.com/watch?v=qkxnltmzrJA
https://www.youtube.com/watch?v=-RsWqJE2NSg
Robot_8.docx
code
' {$STAMP BS2} ' Stamp directive.
' {$PBASIC 2.5} ' PBASIC directive.
'**************Variables**********************
Speed CON 115
RESET_DSMC CON 15
OUTPUT 14
LOW RESET_DSMC
PAUSE 10
HIGH RESET_DSMC
PAUSE 7000 ' Code Start Delay
'**************Main Code**********************
Main:
DEBUG"Frwd"
SEROUT 14,32,[170,9,10,Speed] 'M0 - Forward
PAUSE 1500
DEBUG"Left"
SEROUT 14,32,[170,9,14,127] 'M1 - F Apply Right Brake
PAUSE 1900
SEROUT 14,32,[170,9,14,0] 'M1 - F Relese Right Brake
DEBUG"Frwd"
SEROUT 14,32,[170,9,10,0] 'M0 - Forward
PAUSE 2000
SEROUT 14,32,[170,9,10,Speed]
PAUSE 1000
DEBUG"Right"
SEROUT 14,32,[170,9,12,127] 'M1 - R Apply Left Brake
PAUSE 1700
SEROUT 14,32,[170,9,12,0] 'M1 - R Relese Left Brake
SEROUT 14,32,[170,9,10,0]
PAUSE 2000
GOTO Main
/code
Unfortunately it does not meet the criteria of the "one servo" challenge because you are using three actuators - one motor and two muscle wires.
No matter how this all turns out. It has been an educational and interesting trip. I will be returning from vacation at the end of the month. Hope to see some more entries when I return.
Thanks to all for your support.
You could make that argument, but all the discussion has been based upon one "thing" that is actuated. If I were to use multiple solenoids to drive a robot it would not meet the spirit of this challenge even though the number of solenoids allowed was not mentioned. Besides, muscle wire meets the definition of "motor".
Motor: a machine, especially one powered by electricity or internal combustion, that supplies motive power for a vehicle or for some other device with moving parts.
At any rate, I like what you have done and hope to see more from you.
When we return from vacation I will post this project in more detail on the Projects forum.
Great job calibrating those turns, impressively consistent 180 degree turns. No one else has used Nitinol, the thermal lag poses its own problems. Well done!
I would have surely thought the the "Brain Trust" would have made an entry by now. That is those of you that work with Stamps and code full time. This is a winter hobby for me, along with my model railroad. Spring Summer and Fall it is farming and antique tractors. I will be off grid so to speak for the next few weeks. My be able to check in from time to time? We are leaving snowy North Central Ohio this morning for Eastern Tenn. See you when we return:)
The moving mouth on the robot at in the video below at 0:44 caught my eye. It appears to be a rubber band moved by 4 interlocked gears and gives a really nice motion. That could be moved by a single servo, or motor, or even a solenoid for faster response. About as simple as mechanisms get.
Note that it would work MUCH better using a Parallax controller, which would imbue it with near AI-capability.
Maybe symmetry is much more an aesthetic need thank a functional need? It does seem to be able to get around within its limitations.
I'll have to check out the robot build videos. It looks like a nice collection of simple robots that would be fun for kids (big and small!).