Robowranglers 2014: Vader

[RachelDoby]

Originally Posted by Electronica1

I am thinking the same thing, but I am having issues see how they are getting enough force to give the wheel traction because won't most the weight still be on the 4 outer wheels?

[mwtidd]

I noticed a rangefinder on the front of the bot. Could that be an autocatch feature?

[Duncan Macdonald]

Originally Posted by lineskier

I noticed a rangefinder on the front of the bot. Could that be an autocatch feature?

I would put my money on detecting ball acquisition in auto.

[RachelDoby]

Originally Posted by BigJ

Come now, we all know that in his time as Darth Vader he only used one lightsaber. I suggest one of the el toro arms be taken off.

We tried to intake with just one lightsaber. It doesn't work as well as we'd hoped.

The team was inspired by the look of the intake to create a Star Wars theme. After deciding on the design, we voted on the robot name. Thus, Vader was born.

Originally Posted by techtiger1

Really 148 went with that collector.

We were inspired by the BOOM DONE intake, El Toro. After testing lots of different intakes, we decided that this design was best fit for all of the things we wanted to accomplish. As you can see, we are not the only team that felt this way.

Originally Posted by lineskier

I noticed a rangefinder on the front of the bot. Could that be an autocatch feature?

Yes, the range finder is an autocatch feature. Our operator holds down a button when catching is appropriate, and when the balls lands in our cradle, the lightsabers close onto the ball to secure it.

Originally Posted by roystur44

Nice job,

How does the pneumatic controlled tensioning for the catapult work out? I see it's on a pulley. Do you get a good variation on a shot?

We have two surgical tubing settings, one normal, and one we refer to as "The Force". The normal one is when the cylinder is retracted, and for longer shots we "use the force".

[Electronica1]

Originally Posted by RachelDoby

So... I guess this means BJC was spot on. I just have to ask, why?

[Jeffy]

This is awesome. I appreciate the early post. The subtle changes over the "BoomDone" robot are awesome and are clearly well thought out. Good luck this year!

[Tom Line]

Originally Posted by Electronica1

I am thinking the same thing, but I am having issues see how they are getting enough force to give the wheel traction because won't most the weight still be on the 4 outer wheels?

It depends on the angle of the fork. As the wheels turn, if they are geared correctly, they will actually try to walk down more under the robot and put additional force on themselves. Think of the way that a rear wheel drive car transfers weight to the rear when it accelerates. In this case you aren't shifting the robots weight, you're using the leverage of the drive to push down into the floor harder.

As to the why: every tried to get 5 legs of a stool all the same length? Articulating that wheel is necessary - pneumatically or otherwise. I'd guessing this is a way of not using more pneumatics.

We have a little bit of familiarity with a slide-drivetrain. We tried one in 2008 but we hard-connected the wheels to the frame and quickly discovered why you absolutely MUST have mechanical compliance to insure all the wheels are on the ground. What they have here appears to be a refinement of their 2010 drivetrain.

[PAR_WIG1350]

Originally Posted by Tom Line

As to the why: every tried to get 5 legs of a stool all the same length? Articulating that wheel is necessary - pneumatically or otherwise. I'd guessing this is a way of not using more pneumatics.

That makes so much sense.

[Abhishek R]

Originally Posted by Tom Line

As to the why: every tried to get 5 legs of a stool all the same length? Articulating that wheel is necessary - pneumatically or otherwise. I'd guessing this is a way of not using more pneumatics.

We have a little bit of familiarity with a slide-drivetrain. We tried one in 2008 but we hard-connected the wheels to the frame and quickly discovered why you absolutely MUST have mechanical compliance to insure all the wheels are on the ground. What they have here appears to be a refinement of their 2010 drivetrain.

Could you expand a bit more on why the hard-connected version didn't work and why the center wheel must be articulated? It seems to me if you just had it dropped enough the hard-connection would work.

[Tom Line]

Originally Posted by Abhishek R

Could you expand a bit more on why the hard-connected version didn't work and why the center wheel must be articulated? It seems to me if you just had it dropped enough the hard-connection would work.

Abishek,

It's impossible to have all the wheels touch the floor at the same time, because the floor isn't perfectly flat. As a result, there are times where a non-articulated center wheel will be lifting one side of the drive train off the floor, so that you end up going in circles when you try to drive forward.

I can't see the mechanism well, but I wonder if it doesn't use torsion springs to return it to level so it isn't touching the floor when it isn't running.

Electronica1: I'd venture a guess that your drifting hypothesis is correct. They've seemed to enjoy drifting - I remember them doing it quite a bit in 2011.

[Electronica1]

Originally Posted by Tom Line

As to the why: every tried to get 5 legs of a stool all the same length? Articulating that wheel is necessary - pneumatically or otherwise. I'd guessing this is a way of not using more pneumatics.

We have a little bit of familiarity with a slide-drivetrain. We tried one in 2008 but we hard-connected the wheels to the frame and quickly discovered why you absolutely MUST have mechanical compliance to insure all the wheels are on the ground. What they have here appears to be a refinement of their 2010 drivetrain.

I meant why as in why do this method over, lets say, spring loading it. I understand with H drive you want to have the center wheel always against the ground, however, my team's FTC team did an h drive with the center wheel drop a 1/16 of an inch and it worked pretty well. I am just curious about why use a "floating" center module rather than a spring loaded module? Was the reasoning so they could drift when the center motors were not running?

[APettinger]

Tumbleweed, Tornado, Armadillo, Raptor, Scorpion, Viper, Vader!?

[geomapguy]

In awe!!

[P.J.]

Originally Posted by APettinger

Tumbleweed, Tornado, Armadillo, Raptor, Scorpion, Viper, Vader!?

I noticed that as well, why the deviation from the Texas theme?

[Basel A]

Originally Posted by P.J.

I noticed that as well, why the deviation from the Texas theme?

Raptor = Texas? Or Tornado? This isn't a deviation.