Here is my first go around with Sketchup. I realize it SUCKS, but I can't figure out that dang rotate tool. My thought is that a rack gear would be moved by a servo and move the gears in the way of the motor gear.
Here is the part that is up in the air. Since cone gears don't exist (or aren't easily attainable) I thought it would be more fun if the robot had to use a clutch to move a gear away and put it back onto these gears to make it shift. A cone gear would be smoother, but this will be more of a challenge ;) This project should get some more attention when my extra servos and rack gears come in the mail.
I know it sucks… they are I know it sucks… they are on an axle that connect the motor to the wheels. There will be a gear on each side that match up to those gears which will shift depending on which gear you want the bot in. I realize the drawing SUCKS! When I get back in town in a couple weeks I will try to prototype it better. I am waiting on some rack gears I ordered to handle the shifting.
Yes. This stands a good chance of working. I have used a servo to drive a pinion gear on a rack for a steering mechanism. The good thing was it din’t need a lot of torque as the required torque reduces when you’re moving forward.
Question: If you have (for example) three gears on your “top” axle and you move them back and forth across a “drive” gear, how will you get the different sizes of gear to mesh? I mean, if the spacing is such that thelargest gear meshes, then the smaller gears won’t contact the drive cog unless you employ a spring mechanism, or something (like a derailleur).
I was goign to use a second I was goign to use a second servo that pulled the gear off of these gears and pushed it back on. Depending on which gear was in drive the servo would move more or less.
I completely agree, Sketchup has not bee good to me either. I mentioned that in the Help Designing Your Robot forum.
“Our deepest fear is not that we are inadequate. Our deepest fear is that we are powerful beyond measure. It is our light, not our darkness that most frightens us… -Marianne Williamson
That makes one of us! I That makes one of us! I liked the idea of using different gears instead of a cone gear. I would love for the robot to red line and have shift shock. Maybe I can make a robot that granny shifts I thought it would be cool to make it using a remote control so it could shift when racing other cars.
Like I said the drawing Like I said the drawing sucks. I need to spend some quality time with sketchup to figure out how to easily rotate and move stuff where I want it. My servos should be on my doorstep when I get home. The last barrier is how to move two gears away from the main gears (one on both side of the gears that move back and forth) at the same time. I’m thinking springs or pullys should do the trick. The springs would make sure both sides engaged…
No way to drive "The Fast and the Furious" is no way to learn to drive. Apart from that "shift shock" would be just as bad for a sensitive piece of electronics as it is for a car engine. Granny shifts are not an option unless you want to go to the extentof building a synchro mesh. Are you even going to have a clutch?
I absolutely don’tr want to be discouraging because I would LOVE to see this work, but I’m concerned that in order to make decent use of a gear shift mechanism, the robot would need to have the capability of building up a good momentum. I’d be concerned that the polycarbonate (?) gears migh wear out bloody quickly if they’re rubbing together and not engaging. I think the suggestion WILL work, but maybe not for very long!!
Ive thought about that and Ive thought about that and if they grind too much I can have the gears in the middle and on both sides have a gear (or just a wheel) with a rubber band on it for friction so it doesnt grind. When I start tinkering I’ll tackle the little problems.
Ok so I got everything soldered onto perfboard and the servos don’t seem to work. I’ve tried 3 of them so I know it isnt an issue with them. Does the Picaxe 8m support servos the same way 28x does?
Wha? With the 8m you can’t Wha? With the 8m you can’t use servo? I know you cant with 8 (wont compile). Do you have a link? I’m not using a project board. I guess I could take the 8m off and use a 28, but I really wanted to use the 8m
I
I thought it would be cool to make it using a remote control so it could shift when racing other cars.