Fitting in the scoring zone (dr4b)

As we know, the scoring zone spans 10 inches across, with a scored cube occupying 5.5 inches of that space. That being said, there are a number of intake approaches to fitting a cube within the zone all with their own drawbacks. I’m curious which method the community favors.

The first method is internal stacking, meaning the cube is contained within the robot. This requires a side of the drivetrain to be 4.5 inches and realistically must be even smaller in order to be viable. Tray stackers may not have a problem with this, but even the most compact dr4b’s will have width issues assuming they stick with unshaven c-channel.

(The following is dr4b specific)
The next method is a fold out mechanism, which can provide more clearance, but still requires the drive train sides to be less than 4.5. However this puts more stress on the lift (decreased leverage) and throws the weight distribution of the robot. Reliable locks/fold out mechanisms are also a little harder to design.

Another method is turning the intake 45 degrees. This alleviates drive train side constraints to a degree, but you are still left with the same issues previously mentioned (leverage and locking). Internal 45 degree intakes will cause the drivetrain to hit the wall before completely scoring the cube and are therefore not viable.

The last method that seems viable to me is a shortened drive base which provides more clearance for the intake, and no folding mechanisms are necessary. There are also no drive train width constraints. However, this sacrifices lift height/lift linearity and makes the robot more susceptible to tipping.

Which method do you guys think will be the most reliable for easily fitting stacks into zones?


My current belief is that having the forty five degree turn in conjunction with a slight moving forward of the cube holder would be the best. If the center of the cube is behind the front of the robot, than the cubes wouldn’t cause the robot to automatically rip over, as they would be behind the front wheels or top stoppers. It should give enough clearance that the robot wouldn’t bump into the barrier. Leverage on the lift would still be a problem but not as much.

This isn’t necessarily the best option, but it is my current opinion.


Horizontal 4 bar on a lift connected to the intake. No whack size constraints needed.

While 81K’s last animation looks great, fitting a four bar within a double reverse with cube will be very hard to get down to less than 10 inches. This means they can score 1 stack in the large zone as shown in the animation but can’t do much else. (This is an assumption feel free to correct me if I’m wrong) I do like the idea of a 45degree intake on four bar tho as side constraints are no longer an issue with such a configuration.

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If you talk about rotating it 45 degrees, are you proposing that the entire cube is out in front of the robot? If not, you have to account for the fact that the cube will take up ≈ 7.78 inches rather than 5.5 inches of space horizontally. If you can allow for over 2 more inches, then you should have no problem fitting a horizontal 4 bar, as it can be less than an inch wide on each side.

Yes the cube would have to be almost completely in front of the robot for robot width to not be a factor. Hadn’t thought about that added width sideways tho good point. That makes internal 45 degree intakes unviable.