I wanted to create a self cleaning device that could clean white boards. But the device would stay on the board through vacuum. But it should be one of a very small size. Any suggestions on how I can do that.
My friend said that I should use magnets instead then the device would be driven by the actuators and sensors

 

How is the device going to move to clean the entire whiteboard?

Using vacuum to attach the device adds another level of difficulty. To maintain the vacuum, an airtight seal will be required. When it moves, this seal will be broken and the device may fall off the white board.

This is how I see it. But maybe you can supply more details.

 

Most white boards I know of are made of steel,
a magnet might be easier and much quieter.

 

 

A vacuum would be the way to go, but not with an airtight seal. It will need enough area to have sufficient holding force, and a brush-type seal to reduce the leakage. It will then conllect whatever dust or drippage it creates,

 

A vacuum would be the way to go, but not with an airtight seal. It will need enough area to have sufficient holding force, and a brush-type seal to reduce the leakage. It will then conllect whatever dust or drippage it creates,

Your vacuum is used to collect the dust from erasing, correct?

The TS wants to use vacuum to hold the robot to the whiteboard, instead of the magnets Andrew has shown in his post.

 

Your vacuum is used to collect the dust from erasing, correct?

The TS wants to use vacuum to hold the robot to the whiteboard, instead of the magnets Andrew has shown in his post.

Really, the vacuum could easily do both, if there were dust. so it could work for a chalk board just as well.

 

Really, the vacuum could easily do both, if there were dust. so it could work for a chalk board just as well.

Ok. I just think that the motions in the video, rotation and linear travel, would not be an easy mechanical engineering design. Plus the added weight required to pull sufficient vacuum supporting that weight...

 

A Roomba that operates on the vertical.

Why not not an x-y-z gantry?

 

The vacuum idea could work but would require substantial energy, leading to increased weight (more batteries) and shorter runtime.
The concept requires a fan, blower, or pump to constantly fight the leakage, so it needs to consume energy constantly or fall off.

For example, this blower can manage a static pressure of 1900 Pascals or about 0.27 PSI.

https://www.digikey.com/en/products/detail/sanyo-denki-america-inc/9BMC12P2G001/7622263

If your robot has a base 8" X 8" or 64 square inches, it would suck down with a force of about 17 pounds.

All great, but it takes 74 watts and screams at 69 dB sound level!

 

Such products are currently available, and so it is doable. And I own a consumer-grade laser-level that holds in place on the wall with some sort of vacuum blower. and that runs on 4 AA batteries. Keep in mind this is not an application that requires hours of run time, and so the battery weight is not huge.

 

Thanks folks I used magnets instead not yet tested but I think it going to work

 

Are your white board pens using solvent or waster base ink. Either way I don't think a vacuum will erase the residue.

 

White board pens leave a mark that wipes off with no solvent, just dry erasing. So a mechanical erase system will need dust collection abilities..

 

BUT IT HAS TO MOVE!

MisterBill2, can you imagine how you would modify your laser level so that it could move to a new position on its own?

As I see it, to move, there needs to be multiple suction cups on a wheel, and a way to control the vacuum on individual suction cups. Just to go forward, on each wheel, you’d need to release vacuum on the current cup, rotate the wheel to the next cup and draw vacuum. To rotate, all vacuum must be released except for one, and the wheels move in counter-rotation, reestablishing vacuum. Note the suction cups must rotate on their wheel mounting (causing leakage and increasing the power to maintain vacuum). And vacuum must be maintained in multiple suction cups.

This is very different than using a suction cup to mount a static device, such as a laser level. And the added power plus the engineering cost of designing and building suction cup wheels may make this impractical.

As a final thought, I often see ads for kid’s toy cars that run vertically. Perhaps obtaining one and reverse engineering their mechanism may prove fruitful.

I say all of this regardless of the TS statement that he is going to use magnets, just because the details of engineering a vacuum solution is intriguing

The vacuum idea could work but would require substantial energy, leading to increased weight (more batteries) and shorter runtime.
The concept requires a fan, blower, or pump to constantly fight the leakage, so it needs to consume energy constantly or fall off.

For example, this blower can manage a static pressure of 1900 Pascals or about 0.27 PSI.

https://www.digikey.com/en/products/detail/sanyo-denki-america-inc/9BMC12P2G001/7622263

If your robot has a base 8" X 8" or 64 square inches, it would suck down with a force of about 17 pounds.

All great, but it takes 74 watts and screams at 69 dB sound level!

Such products are currently available, and so it is doable. And I own a consumer-grade laser-level that holds in place on the wall with some sort of vacuum blower. and that runs on 4 AA batteries. Keep in mind this is not an application that requires hours of run time, and so the battery weight is not huge.

 

Just to see if vacuum will pick the dried ink off of a white board. Shop Vac pulls 0.5 InHg. Placed the 1-1/4" hose end against the lines on the board. Nothing! When it rubbed along the surface it would break the powder loose and the vacuum would pick it up. So you would need a "sweeper" incorporated with the vacuum.

 

Most white boards I know of are made of steel,
a magnet might be easier and much quieter.

I've got several whiteboards that are nonferrous. It all depends on brand and style.

 

Just to see if vacuum will pick the dried ink off of a white board. Shop Vac pulls 0.5 InHg. Placed the 1-1/4" hose end against the lines on the board. Nothing! When it rubbed along the surface it would break the powder loose and the vacuum would pick it up. So you would need a "sweeper" incorporated with the vacuum.

The vacuum in this post is NOT intended to remove the dry erase marker. It was to hold the robot eraser vertically on the whiteboard, while allowing the robot to move on any direction.

The TS design already incorporates a sweeper to actually erase the board.

 

Really, the vacuum could easily do both, if there were dust. so it could work for a chalk board just as well.

Doing both is actually pretty contradictory. To get any significant holding force you need a static vacuum with very little airflow while to get any significant cleaning power you need a very dynamic vacuum with quite a bit of airflow. Unless you are throwing quite a bit of power at the vacuum pump it's difficult to get both at the same time.

 

I'm surprised no one thought of making a mechanism to tilt the board horizontal while it is being cleaned. but yet again this is only the 20th post.

Thanks folks I used magnets instead not yet tested but I think it going to work