pic: RoboSpartans week 3



Here’s what we’ve got going on so far,

Practice bot drivetrain and prototype over the back dunking arm.

Geared for 17fps on the mecanums.

63:1 mini cim on the arm on 22t sprockets.

The real arm will be plasma cut out of 1/8" aluminum.

Here’s a video of it in action with drivetrain and arm running at 50% power


Still a lot of work to do on the intake and arm

Looks great! That looks like a really simple, efficient mechanism for tossing power cubes in the switch.

Seeing as you prioritize the switch, what is your strategy for autonomous? If you are set up on the wrong side of the switch, do you plan to drive to the correct side in front of the switch, to the correct side around the outside of the switch, or just cross the auto line?

Another question: Do you plan to focus on your switch or the opponent’s switch in teleop?

Good luck in competition!

For autonomous we haven’t figured out what we are going to prioritize yet, we will definitely cross the line minimum, and with the mecanums stafeing to the other side is pretty easy it will just require some coordination with our alliance partners.

We ended up with this design because we wanted to floor load cubes, do the vault points, and also be able to do both switches, and seeing how important the opponents switch can be we want to do portal cycles, we also are going to have a climber that is not on the chassis yet.

Sounds good!

What is your plan to climb? Are you going to have single-hook type mechanism to take up less room, or a double-hook / wider mechanism for more stability?

We’re kind of in the same boat on the climber; we are planning to do the climber, but we have not implemented it yet.

We have a few prototypes built, most likely single hook because we don’t want to take up so much room on the rung.

Hook delivery mechanism and winch

Can you actually drive up onto the platform? If you can how much clearance do you have from your frame to the platform when going up?

It goes right up and down with the 6" mecanums, doesn’t get stuck, it also worked with 4" mecanums but the students wanted a little more clearance so we redesigned with 6".

The 2*1’s don’t even touch the platform with the 6" wheels, but the clearance is just enough so that it doesn’t, with the 4" wheels it scraped the ramp but still went up and down.

Edit" I imagine if we were “long” configuration it might scrape. It also goes up the ramp strafeing

That looks like a good set of features to shoot for.

What are the pieces of surgical tubing (?) for? Counterbalancing the weight of the Cube? Are they effective?

What braces the two vertical pieces of tubing? At about 0:36, they can be seen rocking back and forth relative to your chassis.

Does the loading and dumping work still properly with bumpers installed?

We haven’t tried with bumpers yet but I’m not worried about the cube still going into the switch, if you are moving the robot with any speed it gives it pretty good forward velocity.

The surgical tubing is to help counterweight the arm, it does okay, it is not set up in an ideal way to get the most out of the tension but it helps when the arm is at and near vertical to keep it from slamming back down and trying to skip the chain on the sprockets.

The rocking back and forth of the arm was caused by us not tightening the mounting bolts tight enough ( we tend to use a drill with a socket adapter and turn the clutch setting down) it turns out when it was mounted originally the clutch setting must have been very low because I came back and tried it with an actual wrench and was able.to get another 3 turns on the nut before it started to crush the tubing (a mistake on our part)

We tightened the mounting nuts properly and added a gusset and vertical bolts to hold everything down nice and tight.

Check my YouTube channel for a second video after we fixed those problems.

Cool Videos, it’s very cool to see other team’s concepts coming to life this early in the season! That’s a pretty nice field setup, is it an Andymark Field or something custom?

We have a full field setup, I believe it’s the border that andymark sells, our entire school district share a pretty cool building, so we have 5 teams in there right now