pic: 6-sided tank drive

[g_sawchuk]

Originally Posted by cxcad

This design is helpful for avoiding t-bone pins and defense in general. Also hexagons have a greater area to perimeter ratio.

Ah, good point, although T-Bone pins are rather rare. However, would the bot be able to play an effective defense? For example, if the objective was to T-Bone a bot of the other alliance, it would require rather exact precision as to hit the bot right in the middle of their side.

[BBray_T1296]

Originally Posted by GrifBot

Ah, good point, although T-Bone pins are rather rare.

I saw them happen quite a bit this season. Robots waiting for the ball from a human player after a truss were prime candidates for being bulldozed back to the inbound station

[AdamHeard]

Originally Posted by GrifBot

Ah, good point, although T-Bone pins are rather rare. However, would the bot be able to play an effective defense? For example, if the objective was to T-Bone a bot of the other alliance, it would require rather exact precision as to hit the bot right in the middle of their side.

Not necessarily, if they are hit square to an angled face, at least the drivetrain is not perpindular to the t-boning robot.

T-bones happen a LOT at the high level of play in certain games.

[g_sawchuk]

Originally Posted by AdamHeard

Not necessarily, if they are hit square to an angled face, at least the drivetrain is not perpindular to the t-boning robot.

T-bones happen a LOT at the high level of play in certain games.

Fair enough. It is true that they happened this season a lot, but this was due to the lack of mobility some robots had as they waited for the ball from the human player. On a good driver, t-bones tend not to be effective as a good driver will stay in motion as much as possible.

[AdamHeard]

Originally Posted by GrifBot

Fair enough. It is true that they happened this season a lot, but this was due to the lack of mobility some robots had as they waited for the ball from the human player. On a good driver, t-bones tend not to be effective as a good driver will stay in motion as much as possible.

There must have been some AWFUL drivers on Einstein this year.... and 2011... They were getting T-boned all the time!

Someone get these teams some better drivers

[g_sawchuk]

Originally Posted by AdamHeard

There must have been some AWFUL drivers on Einstein this year.... and 2011... They were getting T-boned all the time!

Someone get these teams some better drivers

It really depends on the game. It's true, this year was difficult to avoid being T-boned as most robots were incapable of driving right by the human player station without stopping and successfully getting the ball. Mixed with that and the fact that it's hard to move and pass the ball, it was one of the better years for t-boning, but still, t-boning is not what I would consider a very effective defensive strategy most years.

Originally Posted by GrifBot

It really depends on the game. It's true, this year was difficult to avoid being T-boned as most robots were incapable of driving right by the human player station without stopping and successfully getting the ball.

Mixed with that and the fact that it's hard to move and pass the ball, it was one of the better years for t-boning, but still, t-boning is not what I would consider a very effective defensive strategy most years.

Since Adam is too modest to boast about his team ( ), I'll be the one to inform you that that is a very dangerous and mostly incorrect statement to make.

[tickspe15]

If tbones were rare and could be easily avoided by good drivers you would not see teams like 254,971,973,148,1114,118,1730,33 and countless other elite teams dedicating engineering hours, money and weight to mechanical aids to get out of pins.

This year we were caught in pins constantly and it slowed us down significantly while simultaneously wearing down our wheels. Often less high scoring teams don't face the same level of defense as their higher scoring counterparts so their robots weaknesses are never exposed.

[Abhishek R]

Wouldn't a hexagonal shape limit how close you can get to the outside walls of the field? I'd imagine if you skim the wall, you would end up being spun in some direction.

[evanperryg]

Originally Posted by Abhishek R

Wouldn't a hexagonal shape limit how close you can get to the outside walls of the field? I'd imagine if you skim the wall, you would end up being spun in some direction.

In some cases, this is good. Some bumper materials have a lot of friction, so if you get caught up on the wall, it can be a pain to get away.

Originally Posted by tickspe15

If tbones were rare and could be easily avoided by good drivers you would not see teams like 254,971,973,148,1114,118,1730,33 and countless other elite teams dedicating engineering hours, money and weight to mechanical aids to get out of pins.

I agree that tbones are very common and drivers should be prepared for them, but I don't think I've ever seen a team make a mechanism specifically to break pins.

[Arpan]

Originally Posted by evanperryg

In some cases, this is good. Some bumper materials have a lot of friction, so if you get caught up on the wall, it can be a pain to get away.



I agree that tbones are very common and drivers should be prepared for them, but I don't think I've ever seen a team make a mechanism specifically to break pins.

FRC 1114- drop down omni wheels

FRC 118- Drop down omni wheels

FRC 971 - Unique chassis shape

just 3 off the top of my head

[Zaque]

Originally Posted by Arpan

FRC 1114- drop down omni wheels

FRC 118- Drop down omni wheels

FRC 971 - Unique chassis shape

just 3 off the top of my head

I believe 1986 had a drop down omni wheel up front also.

[Boe]

Originally Posted by Arpan

FRC 1114- drop down omni wheels

FRC 118- Drop down omni wheels

FRC 971 - Unique chassis shape

just 3 off the top of my head

As well as a large number of teams using lower friction bumper materials, off the top of my head I can think of 971, 67, 1678, 1717, 254, 148, 1114, and 2056.

[Andrew Schreiber]

Originally Posted by Boe

As well as a large number of teams using lower friction bumper materials, off the top of my head I can think of 971, 67, 1678, 1717, 254, 148, 1114, and 2056.

In the 67 case I recall it was at least partially for their intake based on what my brother said.

[mrnoble]

My students have spent a chunk of their summer designing a hex chassis 8WD because of this very problem; we saw lots of t-bones, and we contributed to a fair number of them. We finished 3D printing the narrow/wide wheels this evening. I've been researching new bumper materials, and the mixing of materials for maximum benefit whether defending or trying to avoid pins. Great stuff!