Robot to Lead Labor Day Mackinac Bridge Walk
 

Join the Fighting Pi in becoming the FIRST to bridge The Bridge!

FRC Team 1718 - The Fighting Pi welcomes all teams in the FIRST community to participate in this year’s Labor Day Bridge Walk across the Mighty Mackinac Bridge on September 1, 2014

We’ll be accompanying Michigan Governor Rick Snyder in leading the way, along with our specially designed Bridge Walk Robot. Come on out, walk the bridge, and help us promote FIRST in northern Michigan. Due to security reasons, only members of Team 1718 will be allowed to join the Governor’s group, but all walkers can discuss FIRST and robotics during the five-mile journey.

Date: September 1, 2014

Time: 7:00 a.m.

Location: St. Ignace – Mackinaw City, Michigan

For information on transportation and parking, see the following link - http://www.mackinacbridge.org/annual-bridge-walk-7/

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

I wanted to update with a picture of the robot we built which will be leading the way for the walk across the Mackinac Bridge on Labor Day.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

This is really cool and so is that robot with your mascot!

But I have to ask, Does that robot come with a blade attachment?

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

with eyes?

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

Soooo tempting.... must make dozer bot....

Watching them put this together was pretty awesome. We've never made anything like it before that is on/offroad capable. It's pretty happy climbing curbs, and they did a lot of testing (and jogging) to make sure that it could travel the right distance at the right speed.

It even has cruise control - with a deadman switch for safety.

They're using an on-board laptop and a wireless x-box controller to control it during the walk. The bonus is that if it goes out of range or the controller is disconnected, the driverstation automatically disables. Safety FIRST.

I know we've had 8 batteries on it (it's designed to actually have more, I believe), and it's perfectly happy driving with someone on top of it because the drive hardware is steel and well supported.

Bonus points if you can spot the error on the robot in the picture.....

Fun fact: According to the design and build teams the the solar panel can supply something like 60% of the power required to drive on level ground on a very sunny day.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

I'm going to have to guess that front left frame covering is bent out?

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

Last I checked, 1718 was not the Fighting Tau. Admittedly something may have changed since... Or someone took a little liberty with how they fit the logo onto the robot. (And this time, I don't think programming can be blamed...it's obviously a marketing problem!)


Either that, or Dozer doesn't have a cantilevered main drive shaft.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

I know it sounds crazy to think 8 batteries might not be enough, but I would recommend walking five miles with it to check and make sure it will make the trip. We had our Dozer bot out for a two mile parade and it only made it 1.5 miles! We ran an Optima yellow top deep cycle battery and didn't do much for turning or crazy driving. We were down to 9 volts and were dropping communication left and right. Luckily we had a pickup truck to do the heavy lifting. Solar panels would have been a welcome addition for us. Our next update is to drop the C-rio and go to a 8 channel RC control system.

Oh! And a tire pump is a wonderful thing to bring too, a slow leak can really slow you down!

Best of luck to you guys and have fun on the bridge! That is such a cool experience for students and I highly recommend anyone who hasn't walked the bridge to give it a try.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

How much do those solar panels actually contribute to the electrical supply to the robot during the walk?

It seems hard to imagine that you would get a whole lot of power from them given the relatively small quantity, and the demands of our FRC robots.

Of course, even a minor increase in range is beneficial.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

You built your Centaur backwards.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

2 Batteries took this robot 4.5 miles (before we stopped). We've actually been running it on the jogging trail (with hills) at our local Metropark to verify it has enough distance - 8 batteries took it much, much further.

FRC bots generally take very little power if you're driving in a straight line with no secondary mechanisms running. We've checked amperage and found that one side of the drivetrain pulls 4-5 amps running on flat ground.

The solar panel can actually supply a decent chuck of power while the bot is running. We haven't tested the panel output, but I expect the panel to give 50-75 watts (it's rated to 250 at max sun conditions). That's around 50% of what the bot takes to run on flat ground.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

*snicker*. Yeah - fighting Tau.

Check out the 'right' hand of the Pi Guy. The thumb shouldn't really be there...

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

Hmmm...I never even noticed that that wasn't actually a Pi symbol. However, the bottom half of the Pi Guy (Tau Guy...that just doesn't sound right) will be covered with a bridge walk t-shirt.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

FRC team 3436, the fighting tau! :)
And Pi is still wrong... http://youtu.be/jG7vhMMXagQ

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

I didn't hear it, but my wife said the governor mentioned the robot while being interviewed on WJR (Detroit radio station) before the walk started.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

The Bridge Walk was a huge success. We had tons of coverage promoting FIRST and it even ended up on a few National News Sites!

We have a few pictures and there are articles all over about the walk. Most are just using the AP Feed for the article.

In the end we ran with 7 batteries in the robot with only 6 turned on. We were able to go much faster than the walkers, we may have been able to beat the joggers that started 30 min before! Level ground we can reach 8-10 mph.

The kids did an awesome job building the robot, we even did some work during our week long demo at the Armada Fair so tons of people saw how we do it.

In the one picture you can see the Governor behind our group with the robot. Now if we can just get the Gov to wear the Pi shirt to the State Championships next year that would be awesome!

Overall it was great to get out and promote FIRST and STEM the fact that we were able to do it with Governor Snyder just made it even better.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

It should be noted that, as with many newspaper articles, there is an error...the AP reported that the robot was built by students from the Macomb International Academy which is incorrect. The robot was built by students from the Macomb Academy of Arts & Sciences which is part of the Armada Area Schools District.

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

Nice Job Pi!

https://www.facebook.com/wxyzdetroit...type=1&theater

Re: Robot to Lead Labor Day Mackinac Bridge Walk
 

I wanted to add some more technical information here. About the Robot.

We used 8" AM pneumatic wheels, which worked extremely well on all surfaces. However, keep in mind that the wheels have some compression, so if you choose to use them, you may have to play with center drop amount or/and air pressure. Of course, most outdoor surfaces aren't as grippy as carpet either.

We used a single CIM per side on the robot. We considered using 2 CIM's per side, but in the end the performance of single CIM's was just fine.

We used 8+ batteries simultaneously on the robot. Safety was a big factor - that many batteries can create a decent amount of amperage. To protect against that, each individual battery had it's own 120 amp main breaker, and then those wires met at a single 120 amp main breaker that protected the electronics.

We actually put a laptop on-board, then used a wireless microsoft X-box controller to drive the robot. We had an inverter available to plug the laptop into power from the batteries: I'm not entirely sure if they used that or not.

The photovoltaic cells were 19V with a anti-backfeed charging regulator. Some day we'll get around to seeing how much this actually helps charge the robot. With multiple batteries, the amp or two we might get out of the cell divided down really is little more than a maintenance / trickle charge when the robot isn't in use.

I'm going from memory, but I think the top speed was around 8-10 mph, using the single cim per side through a cimple box with a sprocket reduction to the wheels. Talons were used as the speed control.

A "cruise control" was written which was little more than a hold-current joystick position. Pushing and holding a trigger while driving saved the joystick's current position, and then the right joystick was programmed to 'trim' speed and balance by making incremental adjustments to both motors when it was pushed. When the cruise control button was released, all outputs set back to zero as a safety precaution.

If you have any questions, PM me (since that emails me).