I been debating for quite a while on which lift to use. A 6 bar or RD4B. I have built a 6 bar and it works. But this year competition a 6 bar is not as effective. So my question is where to place the motors. I can only use 4. Also do need two motors near the gear or not. Thanks in advance
you literally only need 2 motors for a double reverse 4 bar this year since the cone is so light. I put them right on top of the top 84 teeth gear in the middle with a lot of elastic tubing
What on the tower not the gear
First off, don’t be so quick to count out the 6 bar as an option. It may not be as effective as a rd4b, but that doesn’t mean its a bad choice, especially considering you seem to have trouble building a rd4b. It’s never a bad idea to try new things and innovate options that may not be popular, after all, that’s how the greatest ideas are formed. But if you would like to go with a rd4b, there are plenty of pictures and videos of them in effect, so you can just use a motor configuration that has worked for others. 4 motors are more than enough, so you’ve got room to try pretty much whatever you’d like.
I saw this video Vex robotics competition In The Zone 5039B 7090A 7090B - YouTube and I don’t see any motors near the gear so how does that work?
So their motors are on the tower. The gears are only to move the top stage of the lift at the same time as the bottom. This is just a different version of a RD4B.
Ok thanks this makes sense
Another question what height it should be able to reach
I would suggest that you do your own game analysis and decide how many cones do you need/intent to stack.
And once you have decided on that, you can start calculating the height of your lift.
@meng thanks so I’m thinking may be 40-45 in
Why that height?
Cause I have 45 on a 6 bar. What your suggestion
but the main point is - how many cones do you intend to stack? and why that specific number of cones? is it because you have done your analysis and think that specific number of cones will help you to win?
This is what I was getting at.
So how high for around 6 cones
6 cones on a mobile goal is around 26 inches.
So here’s a handy dandy chart for lift heights on certain cone stacks. Have fun
So 45 in will be enough for 6 cones on the stationary goals
I would start practicing with your six bar and use it your first competition, and then build a DR4B/bowtie and use it as the season goes on.
Ok that sounds like a good plan