Team 1261

The Crimper seems to be looking good.

Do we have not have enough data on the shipped chassis, height of lower chassis to be able to build a new kicker and mount it on the proto chassis we have now. We could raise the proto chassis frame height some how to match. This would certainly cut down on guessing and fab work at Clemson.

We will be bringing our portable shop and porta electric power though.

freds wrote:The Crimper seems to be looking good.

Do we have not have enough data on the shipped chassis, height of lower chassis to be able to build a new kicker and mount it on the proto chassis we have now. We could raise the proto chassis frame height some how to match. This would certainly cut down on guessing and fab work at Clemson.

We will be bringing our portable shop and porta electric power though.

I like the idea of building a second kicker. If my numbas are correct, the bearing blocks for the kicker are 3" back from the front of the robot. Onto Logan's robot, we can mount a kicker and see if it clear's the lower bar(which I think it should easily do). I'm like 90% sure that we won't have to curve the kicker now that we have the hinged backing working, kinda.

I for the hinged backing, I recommend making it smaller by changing the point of rotation and bringing it lower. We'd have to look through pictures and see how it would adapt onto Tanner's robot.

As for the CAD, by belief is that the bottom of the chassis is 10 inches off the ground, but I can't be entirely sure because on the old robot, we calculated the center of the robot to be 8.(ish) inches off the ground, and that was well into the chassis, so the CAD might be correct.

@Tanner: Can you use the photo scaling program to get the height of the robot? I know it's inaccurate, but I think the differences between 7 and 10 are large, and the photos will give us a better idea of which one it is.

Before the regional, we can easily fabricate the new roller mounts, the lower bar mount, and the flap. We already have the roller and the shaft, and the sprocket.

We should also plan out changes in the kicker. I don't think that we need to make the kicker wide again, but I believe Logan was correct in saying that any kicking we do on the sides will face instability. Regardless the kicker fix is very easy.

I'm still a little worried about the front bar's clearance as we travel over the bump. It has been suggested that we go over the bump backwards, but the bar will hit the bump when come down. I know that the bar sits further back that it did originally, but I'm still not sure if we're getting enough clearance. Worst comes to worst, we make the bar relatively free spinning and add two wheels to the side so that when we go over a bump, the bar folds and unfolds with the bump.

I know when it comes to work, I'm very optimistic in the time frame that we generally do things, but if we prepare everything correctly and plan out the specific Thursday, the robot should be done before lunch.

- Sunny

Regardless of how low the hinged plate is, it needs to be in vertical alignment with the rear of the roller, or bent to be that way. If you think about having the hinge forward, the flat piece would be angled back, back over the roller, and the ball may never hit it or just barely and not enough the 'make' the switch.

I like the big switch in that it is easily adjustable and robust. I dislike that fact that when the switch makes, it has to move some distance back in the other direction to change states again.

I was just thinking, instead of using these limit switches, why don't we use a VEX touch sensor. We used them back in '08 on the lifter arms...they are robust, and will definitely get the job done. And there's no pin that slips sideways.

Not to mention we have like 30 laying around.

Sunny wrote:I was just thinking, instead of using these limit switches, why don't we use a VEX touch sensor. We used them back in '08 on the lifter arms...they are robust, and will definitely get the job done. And there's no pin that slips sideways.

Not to mention we have like 30 laying around.

Eh, we could, but it would lower how much power full power actually is. Well, not really. It could work.

That darn limit switch was definitely was one of the things that I was nervous about during competition. I just felt like it was going to snap off. Like a twig.

-Tanner

Sunny wrote:I like the idea of building a second kicker. If my numbas are correct, the bearing blocks for the kicker are 3" back from the front of the robot. Onto Logan's robot, we can mount a kicker and see if it clear's the lower bar(which I think it should easily do). I'm like 90% sure that we won't have to curve the kicker now that we have the hinged backing working, kinda.

We should also plan out changes in the kicker. I don't think that we need to make the kicker wide again, but I believe Logan was correct in saying that any kicking we do on the sides will face instability. Regardless the kicker fix is very easy.

I think that we should probably build a new kicker optimized to our new setup just to minimize problems that we would encounter while building at palmetto. One thing that we should consider is that the kicker is currently still narrow, and just adding a lower bar will not be a structurally stable as the way we had it before, with a wide frame.

Sunny wrote:I'm still a little worried about the front bar's clearance as we travel over the bump. It has been suggested that we go over the bump backwards, but the bar will hit the bump when come down. I know that the bar sits further back that it did originally, but I'm still not sure if we're getting enough clearance. Worst comes to worst, we make the bar relatively free spinning and add two wheels to the side so that when we go over a bump, the bar folds and unfolds with the bump.

I know when it comes to work, I'm very optimistic in the time frame that we generally do things, but if we prepare everything correctly and plan out the specific Thursday, the robot should be done before lunch.

- Sunny

I think that we might just settle with going over the bump backwards, and allowing the bottom bar to graze the bump. It just seems more important to have an amazing manipulator than the ease of going over the bump. we could let it rotate and spring it backwards so that as we go over the bump backwards, it simply hinges forward and then springs back to its proper position, but this would help only slightly.

I don't think we're allowed to have any non-traction device touch the ground, no?

-Tanner

Tanner wrote:I don't think we're allowed to have any non-traction device touch the ground, no?

-Tanner

Thats what I thought until I saw several teams do it quite deliberately and explicitly. One team at peachtree was designed much like ours, and it had a flexible ball guard that stretched over the bump as they crossed. Also, team 84(?) at their regional every time they went over the bump, they flipped over, and touched the ground when righting themselves.

When they flipped, there were the "laws of flippage" that took over.

A very "easy" solution to this would be to take some vex omni wheels, drill out the center and allow them to ride the ground when the lower bar is at its appropriate position. When we go over a bump, the wheels roll and articulate the bar, and the omnis are official wheels and therefore are *not* illegal traction devices.

- Sunny

http://www.thunderchickens.org/

You can see their roller system really well in that one.

They have the backing sitting in there to stop the ball, and the kicker barrels through that opening. It's definitely curved.

With backing switch, we really don't need to curve the kicker, and with the ball never really being "forced" in a great deal further than the 3" we allow, I think we ought to be alright with our current kicker.

- Sunny