How does the pad “adhere” to the platform. I’m assuming some kind of suction if so where did you source the pad?
The “suction cup” is a 12" x 12" aluminum plate with some industrial strength weather stripping as a seal. Pretty straight forward, nothing too special. A vane pump makes +20 in hg which produces 1400 lbs. of holding force.
Not gonna lie, something about the lighting and the camera angle makes this look photoshopped.
Nice, I assume you took an off-the-shelf vacuum pump and just replaced the motor, but I’ll be darned if I can find one that’ s reasonably light weight that you could do it with. Nice job!
Patience grasshopper, soon there will be YouTube evidence of this bizarre levitation.
I can see where you are coming from, but I can assure you, having seen it in person and up close, it is very real. Like, scary real!
This thing turned by a 775.
I’ve seen it in action at St. Joe. It’s real and it’s spectacular.
Could you provide a link for the industrial weather stripping?
I know it came from Mcmaster-Carr, and I believe (90% sure) it was this one.
The qualities we were looking for were:
- Closed cell
- Pressure to compress
- Wear resistance
- Low profile
- Bounce back
Part number was missing from earlier link. It is 93725K72
I was hoping it would of been something cheap like vacuum pump most other teams use, we currently are using one that required use to cut a 775 shaft in half is this one easier to use with a 775.
The units are available with an integral motor, which must be removed and replaced with a legal motor in order to comply with the rules. We used a 775Pro. We needed to modify the pump shaft to take a bearing for support, and are belt driving it. We print a mounting plate to support everything.
That was a glamour shot–there was a light diffuser off to the left of the photo, but it is nevertheless real. Incidentally, the two small “sticks” coming down from the bottom left of the robot are what we call “kickstands.” They don’t touch the floor when we are up, but are there to catch the robot (or ease its fall) if for some reason the suction fails. So far the suction has been very robust and they haven’t been needed.
Did you guys seal around your custom gasket with any type of sealant as a precaution. How do you guys release the suction also.
The weather stripping, 93725K72, has adhesive backing. We don’t use any additional sealant. We’ve pondered a bunch of ways to reduce the risk of seal failure but haven’t lit on anything practical yet–and so far it hasn’t been an issue. There is some concern about wear to the hab platform over the course of the season and the impact that may have on how well this scheme works. If you choose to follow us down this path, keep that in mind!!! “Your (and our) mileage may vary.”
The vacuum is released with a manual release valve.
My favorite part on your robot is something that resembles a vacuum tube:
It’s not exactly the same as the one pictured here, but I guess it has the same function: keeping the air dry.