Secrets of a 4-Bar Lift

Last Saturday I noticed that many of the most notable teams had 4-bars at the South Texas Regional. Among these are: 2880A “Torbots” and 2344B “Clear Springs Vex Robotics”.

Our team has since decided to scrap our lift due to poor performance at our most recent competition and were curious about 4-bars.

Many teams, including us, have 6-bars and cannot reach the 24" goal efficiently or at all, so I was surprised to see these teams with 4-bars that easily reached the 24" goal.

We were just wondering if there was any particular “secret” to 4-bars, hence the title. Pictures would also be much appreciated if possible.

I was also wondering if there were any other advantages a 4-bar has over a 6-bar.

There are some great advantages over a six bar v.s. a four bar that we have noticed. here they are…
Simpler
Lighter
Easy
Looks a little too easy, and unpredictable
Easier to hang with
and lastly, require less parts.

We spent a long long time perfected the height on our 4-bar and we are not prepared to reveal this to anyone yet,but will release a series of videos after Worlds explaining our Robot’s.
Like us on Facebook, and I’ll tell the Page manager to contact you if you need help. Just search “2880A TorBots” on Facebook!

Thanks for Acknowledging us as a good team, you guys were great as well! Good luck!

Thank you for the information. You were great as well!

Just in case you are interested, I have the footage from the finals matches in a playlist on YouTube (http://www.youtube.com/playlist?list=PLg5oYIpY3b-WUOi1WxAJBADggXfLjEjGg). Sorry if you can’t see what is going on very well, I was far away and had to zoom in at a weird angle.

Thanks for the footage!

4252A did not have a 4-bar. We had a 6 bar. The design of our 6-bar served several purposes during the design we first used it for which are not necessarily applicable to our design at state. I really don’t think either a 4-bar or 6-bar are going to have a serious performance advantage if either are built well. A 6-bar will be a little bit heavier/complex (and only a little bit), and can be more finicky stability-wise but will get you more height more easily with more configuration options. 4-bar will be easier in some fronts but will be trickier to get greater height with.

My apologies, I thought I had seen a 4-bar on your robot.

Ways to make 6bar (or 4bar) higher:
Increase the space between the horizontal bars
Mount the bars higher
Extend the length of the middle horizontal bar (by adjusting mounting for example)

Calculator: http://farce.elementfx.com/liftcalculator/