944A Bionic Bayhawks "Asgard" MK. III Reveal

944A “Asgard” Mark III

Asgard is currently in the third version of its development process. Asgard Mark I was equipped with a chain bar and side rollers. Asgard Mark II was upgraded to include a second set of top-mounted side rollers to intake the large balls, the pneumatics were redone, and the code was completely rewritten and optimized for optimum performance. The current rendition of Asgard has been upgraded with an 8-bar and a set of single strip to prevent bucky balls from falling out of the tray, and the bottom sprockets on the side rollers were swapped out with smaller sprockets.
Base:
4 393 motors, geared for speed
Two direct drive, two chained
Lift:
4 393 motors, geared for speed
8 Bar Arm
9.325:1 Compound Gear Ratio (Speed motors make 15:1 an effective 9.325:1)
5:1 outside, 3:1 inside
Intake:
2 393 Motors, geared for torque
Two large side rollers intake bucky balls and large balls
Pneumatics:
Two pneumatic tanks provide air for one pneumatic actuator which deploys the flip-down intake during autonomous. A future actuator will be added to assist in the hanging process.

During our testing, several issues were addressed. We found that a 15:1 (Effective 9.325:1) gear ratio was an effective combination of both speed and torque, and the 4 motors gave us the necessary torque to hang at a future date. When we upgraded to an 8 bar, the bottom sprocket on the side rollers had to be swapped for a smaller one due to space constraints. We also found that bucky balls had a tendency to fall out of the tray when the robot was in rapid motion, so we added a piece of single strip to prevent the bucky balls from rolling out. An added benefit of this was that we would not need two pneumatic actuators to deploy the flip-down intake, only one.

Future Plans:
[LIST]
*]Optimize Big Ball Intake
*]Add The ability to Hang (In Progress)
[/LIST]

Thoughts?
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Here are some more pictures:
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Looks very nice. How heavy is it?

I dont know If you noticed this or not but, the axle in the 36t gear that transfers to the 12t metal gear, is twisted, you may want to check that out.

other than that the robot looks great :smiley: .

How do you plan on hanging, through a pneumatic assist or a direct pneumatic hang?
axle_twist.jpg

Yeah, we noticed that axle, we’ve been meaning to replace that. And we’ve found the robot can effectively lift it’s own weight, so the pneumatic assist we plan on adding will simply lodge itself in a non-harming way in the arm when the robot is hanging, to prevent it from dropping down when the match ends. The pneumatic will not actually assist in the hanging part.

ok just making sure :slight_smile:

I wish I had pneumatics to use :smiley: , We have been having trouble with a reliable locking mechanism once the match ends,

Robot is looking great! Could you post a video of it in action :D?

Yeah, pneumatics are extremely useful in a lot of circumstances. I’ll try and have a video posted by about this time tomorrow of the robot driving around and getting buckyballs and large balls.

Without having the robot on hand, I’d say approximately 10 pounds. We’ll weigh it tomorrow to double-check.

Edit: On a closer guess, 13-15 pounds may be more accurate.

10 pounds robot will be very light and you do not need Pneumatic system to hang it

I’m guessing it’s more like 14 or 15 pounds just from looking at it. I could be wrong, but it is almost certainly heavier than 10.

The pneumatics are not to hang. They are used to prevent the robot from falling back down after motor power has ceased to be applied A.K.A. the end of a match.

We went back for a second analysis, it’s probably about 15, yes. We’ll have an exact weight on here tomorrow.

15 will possibly be the minimum because two cylinders will weigh about 2 pounds

I am fairly certain that the tanks weigh .5 lbs each.

Yeah, the vex website lists them at .68 lbs each, so you’re a bit closer.

If you plus pistons, tubings, screw, nuts, it will add up.

Sooo… you have 2 reservoirs on your robot but only fire one piston once in an entire match? o.O Am I missing something? You could just use a long coil of tubing to store enough air for one action in a game, or even better, you can skip the coil of tubing and just have the piston filled before the match, then you don’t need to “store” any air at all. Just release what the piston already has. When you get pneumatics to hold the robot when hanging though, you will need to store air in some way (to save weight, I’d recommend the coil of tube).

Unless the piston on your intake is doing more than just releasing the intake? Perhaps tossing the large balls a little bit?

~George

As it stands right now, the 8 bar you built doesn’t give any more height than a similar 6 bar (refer to attachment). If the height you have if sufficient, then I think you should switch to a 6 bar for reasons like friction, ease of maintenance.
8bar.jpg

Actually they are getting about 5 extra inches of height as the bottom bar of the linkage indicates how high it would go and the 8 bar provides more height.

Not exactly, their 8 bar stop early because they have that c-channel sticking downwards. Notice their 8 bar and the 6 bar I drew have identical ranges of motion. You can even imagine them being both on the robot at the same time to see why this is true.