3 robots designs I hope to see this season
 

I am not affiliated with a team, so I have little to no influence on any of the designs of this years game. However, I will be watching competition and here are the robots I would love to see.

1) Simbiotics 2008 look alike
What I envisioned before Friday:
http://www.simbotics.org/media/videos/2008
What I envisioned after Friday:
http://www.youtube.com/watch?v=C2UA7...layer_embedded

I think having the entire front of a robot pulling in and funneling the balls to a central arm that can only hold 3 balls(per rules), elevate them to a height, and spit them back out would be a great and quick way to score balls that your alliance has either missed or are just loose. Of course, the poofs bot is a little tall, but I have confidence that teams will be able to engineer a way to solve this issue.

This robot will be a game change because it is a relatively easy design that has the potential to score efficiently and quickly. Many high performing teams will have a similar designs and they will love to be alliances with team that can feed them balls. These teams will win matches in qualifications if they can keep control of the balls, and will be considered great robots in eliminations.

2) Half Court Shooter
What I see is a robot that can sit in the alley against it's own bridge(for alignment purposes) and can shoot either high balls or balls with lots of backspin across the court. The purpose of that is to either have a larger target to hit, or to give the ball a push downward when it hits the backboard.

Not only that, but I would love this robot to essentially be a giant net, with the back of the robot being very low to the ground. This would allow the human player to easily bounce pass the ball into the robot, or to toss the ball half court into the robot. Bonus points if the team calibrates the robot to be able to score while on the bridge in the final seconds.

Teams using this design will not rank very high, not because they will not score well; this design means that this particular robot can only score balls that their opponent scored first. There will not be many teams like this(think 469 in 2010) but will be first round picks for eliminations. Think: what if your alliance had a robot that could score all the balls your opponent does after they score them? If you can do that, then you can not fall behind during teleoperated period. This robot will be a game changer. What gets me excited about this design is if both alliances have a robot capable of doing this well, then the scoring will be high and it will all come down to the bridges and hybrid.

3) Bridge Bots
Teams planning on using designs 1 and 2 will probably consider the bridge and attempt to balance, but will be either mediocre balancers or to large/odd weight distribution/not enough experience to balance on the bridge. Not that some teams won't excel at scoring and balancing, but these robots will be able to balance with almost anyone and will be experts at it.

This robot will be small, think of 148 in 2008, but will weigh the max amount. This robot will be able to get onto and locate the center of the bridge. The robot then will be able to tilt the bridge either way without driving in either direction. They will do this with a light frame and heavy weights inside the frame that allow them to shift the center of mass to either side.

If teams ever balance 3 robots, it will be because a robot similar to this was on the alliance. Not to many teams will have this design because you will not be a scoring bot, but these teams will get a lot of attention from other teams.

What will be interesting about this design: Although their capabilities will be quite limited, they may be able to be one of the highest ranked robots at any regional. This is because of the qualification points you get while balancing with the opposing alliance. Winning is fine and dandy, but what alliance would not tell their team mates that had this capability to assist the alliance in elevating to assure you get the qualification points; likewise, what opposing alliance would not agree! This robot will get attention early, and they will be the team everyone remembers from this year.

Feel free to comment on with your own designs you hope to see this year.

Re: 3 robots designs I hope to see this season
 

Very interesting, however, based on the popular designs of a pitching machine bot, half court take a muzzle velocity of 34 ft/sec and full court back corner shot take 50 ft/sec, which is too far for a spitting robot. Only a direct contact bot (throwing) will be able to put enough mechanical efficiency into the kinetic motion of the ball. Also, the goal being so far away, only math will be able to make the shot, not human controls, so this competition is 99% robot.

On the three shot robot, there is absolutely no way to load 3 balls at a time, and shoot all three with a spitting bot or any bot for that matter. The balls simply are too heavy. Also, the bridge bot would take a lot of weight in pieces alone to get the balancing right (i.e. wormgear secondary drive to lock position.). Also, balancing isn't inside it's own special timeframe like the autonomous period is. That means one team will have to sacrifice probably 30 seconds (1/4 the game) to just attempt to balance by themselves. That being said, a competent robot that can score will have more at least 10 points without having to worry about the probably of not balancing. Also, it wont be sabotaged in balancing. If I were the other team and saw someone balancing, i would simply take a 3 point foul and touch the bridge to make it "not supporting all robots) instead of have a team score 10-20 points off a chassis bot basically.

Re: 3 robots designs I hope to see this season
 

Firstly, my team didn't even consider a design that held less then three balls, there are literally hundreds of different ways you could do that. Basically any competitive robot will be able to hold three balls- they are not heavy. Secondly, bridge balancing does not actually require anything more then a something to push the bridge down and a practiced driver. Balancing more then one requires a bit more precision, and three is quite a trick but one is very doable without any fancy stuff (like worm gears?).

And finally, [G25] Robots may not contact or otherwise interfere with the opposing Alliance Bridge. Violation: Technical-Foul. If the act of Balancing is interfered with, also a Red Card and the Bridge will be counted as Balanced.

You need to get your facts straight or you're going to be very suprised come competition season.
Regards, Bryan

Re: 3 robots designs I hope to see this season
 

If I had to choose 3 unique designs...

1. A catapult. We loved ours in 2009 and with some very minor modifications would have played this game better than the game it was designed for. :o Sadly it has been dismembered for other projects. :(

2. A robot that can elevate and use gravity to feed 3 balls in the 2 point goal in one dump. This accompanied with a super fast drive train and a quick ball pick up could be a very reliable partner. I always think a scissor lift is a terrible idea, and almost every year someone builds an effective one. Here's your chance. :)

3. A robot that can move up onto to two wheels like a segway to make room on the bridge for two alliance partners. ::rtm::

Re: 3 robots designs I hope to see this season
 

The motors available in the kit of parts this year have a combined power output of over 3,000 Watts. There is easily enough power to do this.

If you interfere with the act of the opposing alliance balancing their bridge, you get a Red Card and their bridge counts as balanced. (G25)

Re: 3 robots designs I hope to see this season
 

Forgot that rule, but regardless, there will need to be a stop on the bot (worm gears cannot be fed the opposite way to move thus creating a permanent stop to wheel motion). Balancing will be hard even with one robot with no stops on it. And one team would have to make sure the stopper doesn't accidently get inside one of the 15 holes on the bridge. Also, robots are allowed to "block" the bridge if they just happen the stop to shoot in front of your bridge. I understand the field flow of motion cannot be obstructed, but even 10 seconds of moving can affect a chassis balancing team.

And actually holding three balls then shooting them is almost 2.5 pounds to shoot. There is no way to shoot that much weight at one time from 10 plus feet. that is too much torque that when geared down, is too low an RPM even with the CIM motors. Our design holds 2 yet the bot will only weigh around 50 pounds and is an active collector and shooter from literally all spots on the field. A collector in this game may not be worth it since it would be difficult to drive a ball into the narrow side of the bot that has a maximum of 11 inch opening and the wide side (22 inches) where any corners could damage the ball by running over it. (and the ball is also 8 inches in diameter which means a claw in that area would have to be very slender) Also, the driver will be 30+ feet away to gather the balls if it hasn't any in the bot itself which could be facing away from it. The driver is threading a needle.

Re: 3 robots designs I hope to see this season
 

Regarding, Number 3, would that not violate the bumper rule? Unless you meant a small robot with only 2 wheels.

Re: 3 robots designs I hope to see this season
 

3000 watts, but that's combined. You can't mismatch motors and think there will not be binding (for arm robots) or miss matched speeds and spin up times (pitching machine). Also that battery would drain so fast! lol

I would go for the consistency and simplicity and reliability and easy repairs that one arm offers whether it be any type.

Re: 3 robots designs I hope to see this season
 

[R29] only requires the bumpers to be in the bumper zone when the robot is standing normally on a flat floor. The bridge is frequently not flat, not the floor of the court, and this situation would be spectacuarly abnormal.

Re: 3 robots designs I hope to see this season
 

You can use a different power motors in the same mechanism easily without any problems, as long as you match the free speed to within a few percent of each other. For example, if Motor A is 10,000 rpm and motor B is 5,000 rpm and you want to use them in the same gearbox, simply gear down Motor A 2:1 before you interface it with Motor B.

Re: 3 robots designs I hope to see this season
 

But if you geared down one motor, when applying the ball to the system, one motor has more torque that gives more resistance to the ball's inertia. But at the same time, the other motor takes the same resistance to the ball's inertia, but has less torque than the geared down motor so it slows down more and gives the ball an odd trajectory and speed and backspin.

Re: 3 robots designs I hope to see this season
 

I'm not going to get into an argument with you so this is the last time I'm going to post in this thread.:]

1. Build a bridge and try to balance a robot on it, it's not that hard. You really don't need anything special.
2. Those 15 holes are less than 1/4 inch deep. They only go through the polycarb covering on the bridge.
3. You will have a difficult time trying to block a robot that is balancing from it's ally.
4. You are presumably not shooting all of your balls at the exact same time (you would have a difficult time making them all go into the basket.)
5. You do not need a CIM geared down for torque to shoot 8" foam balls.
6. You should not expect to be able to score into a basket from anywhere on the field consistantly.
7. Collecting off the ground in this game is extremely worth it. It's called Rebound Rumble for a reason.
8. Drivers have been "threading needles" for years in FRC. You have to get good at it or expect to loose to someone else who can.

Good Luck in your first FIRST season, and try to stay open to new ideas and alternative perspectives.
Bryan

Re: 3 robots designs I hope to see this season
 

You can shoot from anywhere and make it every time with math :]
And we did until we weighed pros and cons with prototyping and mathematical analysis. Balancing will be a huge challenge considering its worth a lot of points (relatively) and the boards are pretty small for 3 bots. Also, collecting off the ground doesn't necessarily mean something that runs along the ground. Gripping on the holes is considered grappling as well if suction cups are, so I would avoid even touching them. Draw a spreadsheet to find the needed acceleration and muzzle velocity for even 20 feet away. It's some rather big numbers for that 11.2 oz ball. You can block an alley easy if you just rolled over there in the last half minute "collecting basketballs". And when threading the needle, I would rather have my robot thread a needle than a driver. Like a sewing machine versus a hand sewer. Though the hand stitching may look prettier, the sewing machine proves a better more precise, versatile, dependable stitch.

Re: 3 robots designs I hope to see this season
 

FALSE.

If you mix two motors in a given system, and gear them appropriately, they will share the load.

Why?

Say I have a CIM (free speed say 5000rpm for this simplified example, with a torque of 1 units) and a FP (free speed say 20000rpm for this simplified example, with a torque of 0.2 units)

I gear the FP down 4:1 before mixing it with the CIM. The free speeds now match, but the FP only has an equiv. torque of 0.8 - the sum of the stall torques of the two motors geared together is now 1.8 units

When I apply a load to this system, the motors will slow down because there is a load. Say I apply a torque of 0.9 - half of our stall 1.8. Assuming everything is perfectly linear, the motors will slow down to half speed. Because they are geared together, they HAVE TO RUN AT THE SAME (relative) SPEED. Since, at a given speed, each contributes a different amount of power, the power they contribute is approximately correct, the sum of their power output is equal to the load, and given the power output of the motors, the larger motors will contribute more power than the smaller motors. - In this example, the CIM would contribute 0.5 torque units and the FP would contribute 0.4 after gearing (the FP sees 0.1).

You can effectively gear motors relative to one another and add their (geared) torques without much issue, and design the system as if it was a single super motor. To make things even better, most of the motors in the KOP come in pairs, and you can have up to 4 CIM or BB's, so you don't often need to mix motors of different types.

(as a side note, BJC and I wrote up some TI-84 equations/graphs for throwing a ball, and it wasn't as bad as you make it sound, balancing the ramp isn't very hard for a single human-driven robot, and if you are ever in the opposing alley it's a penalty under [G28], even if you were collecting balls)

Re: 3 robots designs I hope to see this season
 

Look I really hate chewing someone out on this forum, I feel that it's destructive to the FIRST environment and goes against Gracious Professionalism, but you sir are off your rocker. Do you really doubt the ability to throw 3 poof balls at the same time?? FIRST Team 95, the Grasshoppers, seemed to have no problems launching 6 balls in the air at the same time in 2006... and that was with 2 FP's... Seriously, I think a lot of your opinions are exactly that, opinions. Please trust the people who've "been there and done it" when it comes to what is feasible. Stating your ideas is wonderful and encouraged, but bashing others' opinions is not GP and over the line. Please back off.