There are many types of robots, from the pusher to the conveyor that picks up six cubes at once. Some of these have their flaws, some of them have their advantages. Here is a list of robots that I have seen thus far:
The Pusher: We ahve all seen this. Some have six wheel drive, to increase power and speed, but can only score a maximum of maybe fifteen points. Five for the autonomous mode on the platform, five at the end of the round on the platform, and then the few cubes they push into the corner. They are annoying little buggers, usually blocking the high scoring robot.
Single Claw/Long Arm: Usually harbors four wheel drive. Has a arm with two with two hear elbows for twice the reach of other robots. One effective mama. If the drivers are use to the controls, I rarely see anyone actually miss with claws. Precision is key with these. But they do lack the ability to be able to pick up six at a time, decreasing the amount of scoring brought forth.
Conveyor: Four wheel drive. Conveyor usually has zip ties (apologies if I spelt that wrong) for mroe effective grabbing. Conveyors, from what I have seen, are the beasts in this competition. They grab six, leave and score for a good minute until they need to reload. Scoring is not AS precise as a claw, but there is definetly a consistency. A draw back is that if the zip ties are cut to short, they are very, very, strong. So strong that they almost launch out cubes, missing the goal. But when you miss only one shot out of six, who’s complaining?
Other than this, I have not seen many other designs out side of these. Some that are different, but definetly on the same premise.
(though i’m not expressing my oppinion) another type of robot I have seen a bit features a horizontal cage w/ an intake-roller opening that grabs cubes from the autoloader and is lifted via 4-bar-linkage, these usually tend to be able to hold around 4-6 cubes and are effective because they can quickly get all 5 of the autoloader’s cubes at once.
Ive been having trouble deciding this myself, as I was able to nearly make it to the finals with a decent claw on a 4wD bot. Had my bot been more robustly built, my alliance would have made the finals. I can’t decide if my bot for the next comp. will be a conveyor or a better claw.
One of the best robots at our scrimmage had a pair of the horizontal treads, it would empty two loaders, holding 10 cubes. It had a offset four bar linkage (front moved more than the bac) and could get up to the 21" goals.
They would move into a goal, drop a single cube and move to the next. They were quick, they could make the round of all the goals in about 45 seconds. Cap and go worked well they were undefeated all day.
One of our robots is a claw on an extendable arm on a 4 wheel drive base. It is very fast, the arm lifts and extends very quickly. They have become very fast, very accurate drivers. They did very well, their focus was to cap the tall goals since most teams can’t easily do them.
For the next meet they are going to make an adjustment in the elbow to make it a little more solid, it should help the small wobble factor. We are also going to look at some operator assist code to tell the robot to place at the high level and let it move into position automatically.
That was just like ours, the capping strategy was great. Two rounds in the playoff heat, my robot got hit and the servo for the claw froze up, so I basically gave up two rounds and almost made the finals.(Lost by ten points to the first place team in an overtime round.)
So a claw may work, but it needs to be robust, in every sense of the word.
I would think two intake rollers similar in design to the NERDS infamous robot from QQ. Yet, I have not seen a robot impliment this design yet.
Also, I have yet to see a robot reach into a goal and descore the cubes. I highly anticipate there will be at least 1 amazing robot to be able to do this in the championships (betting on a chinese team).
I’ve seen something similar to the robot you’ve mentioned - it was fairly effective but very bulky.
As for descoring… I would imagine the only way to descore without puncturing is to get something on 2 sides of a cube (i.e a chopstick design). Since the cubes can be oriented any number of ways inside the goal, you’d have to have a design that makes position irrelevant, which would likely be similar to intake rollers oriented in a circle. This would be big, so you’d have to have amazing driver control.
Summary - very hard to do unless my brain is not functioning well the day before a competition.
In a recent competition, I noticed that claw oriented robots had more capability in blocking the top of goals of any height. Also, since many conveyor oriented robots, aka point scoring beasts, were more designed to control the lower goals, an alliance of a clawbot and conveyor bot seemed to have the most chance of winning a match
-Clawbot takes over a corner, usually 21" and 15" goals, while the conveyor is zipping around taking everything else
-Clawbot had an easier time with keeping the bonus cube
I am still trying to decide whether to put a claw or some kind of intake device on my robot too.
I have seen all of the designs everyone has described so far while watching competetion videos on youtube and I don’t know which would be better. I have weighed all of the advantages and disadvantages mentioned so far and the only thing that I know is that I want to be able to reach all of the goals.
So far, I have a arm with a linkage to keep the end level as it goes up and last night I put together something using the intake rollers that can pick up 3 cubes at a time. However, it can only pick them up off of the field and not out of the loader.
This is definitely not an easy decision and I have seen a lot of great robots.
If anyone is looking for a good robot, trust me, this is it right here. My team is building five robots and two of them are going to the WC for sure, the one that we built anew just recently does this same thing, but it can only slowly get the cubes out of the loader.
Nearly everything on Zippy is aluminum, so nothing is heavy. The only way the driver has flipped it is by going off the platform with the belt lifted and THEN reversing direction half-way down. Other than that, it’s very stable. We have another twin-belt robot in our collection that was over-built and heavy, and it DOES have troubles with tipping. That robot (419) is currently on a major Zippy-inspired diet.
Zippy seems pretty sweet, but I think it’s also effective to have the arm built so that can block the top of any goal. my 2 elbow bot seemed to be good at that. in my imagination i only see zippy blocking goals awkwardly, unless im mistaken.
Zippy’s not intended for defense at all. My thought was that if someone was scoring a goal, Zippy would be off capping other goals. With speed and mobility, Zippy is designed to score faster than its competitors. Since Zippy won’t compete, we won’t know for sure how it would have done in a live match.
The most important thing, IMO, is to have a clear strategy on how to play the game, and then build a robot to fill that strategy. If you think defense is a good approach, then your robot is probably better. There is nearly always more than one good way to build a competition 'bot. Good luck this year!