Overlapping bistable domes to control and shape high strength steel ? (sheetmetal)

[Milacron]

Interesting concept... would be fun to play with a sample.... real world applications ?

Bistabledome.com: flex actuated overlapping bistable domes

Flex actuated overlapping bistable domes (OBDs) are used for paper thin shape sensors, stiffening and shaping thin high strength steel, and a pump that pumps when bent.

www.bistabledome.com

 

[Hightemp]

Nothing like youtube videos published in 2022 which look like they were made in 1981 to make one think crackpot!

The sensor application seems especially insane. How would an array of yes/no switches be better than traditional strain gauges?

But yeah, I'd like to have a piece on my desk to bend back and forth.

 

[eKretz]

Might be nice for sheet metal fabricators that are making complex shapes. Easier and faster than hammer forming.

 

[sfriedberg]

How would an array of yes/no switches be better than traditional strain gauges?

For an honest comparison, you'd need to contrast an array of strain gages against the array of switches.
If you really want to measure strain (stretch) then a couple of strategically located strain gages are great and the results are much easier to interpret than integrating more-or-less discrete deformations at 100 locations. Win for small number of strain gages.
If you really want to record multiple contact positions (as shown in the set of photos on the website first page), then an array of point sensors is great, and yes/now is much easier to deal with than strain gage output. Win for large number of switches.
Within some limits, this dimpling technique offers the potential for having areas of higher/lower resolution (as a sensor) or curvature (as a deformation) by altering the size of the domes.

 

[bistabledome]

Interesting concept... would be fun to play with a sample.... real world applications ?

Bistabledome.com: flex actuated overlapping bistable domes

Flex actuated overlapping bistable domes (OBDs) are used for paper thin shape sensors, stiffening and shaping thin high strength steel, and a pump that pumps when bent.

www.bistabledome.com

Hi, that's my old stuff. Doing a search and I happened to see your recent post.

Re real world applications for bistable domes - just after the recent underwater Titanic disaster I started thinking about how OBD laminates might compare with the carbon fiber and titanium components of that sub in weight and strength, but that's way out of my range.

 

[bistabledome]

Nothing like youtube videos published in 2022 which look like they were made in 1981 to make one think crackpot!

The sensor application seems especially insane. How would an array of yes/no switches be better than traditional strain gauges?

But yeah, I'd like to have a piece on my desk to bend back and forth.

My family and friends have called me a crackpot. The videos were done with early low cost digital camera around the turn of the century.

How would an array of yes/no switches be better than traditional strain gauges?

I don't think using strain gauges could provide true 2D profile and you'd have a lot of analogue data to analyze trying to do it. An OBD sensor row or rows would give digital patterns made for AI pattern analysis. Low resolution, but also low cost with large scale applications.

 

[bistabledome]

For an honest comparison, you'd need to contrast an array of strain gages against the array of switches.
If you really want to measure strain (stretch) then a couple of strategically located strain gages are great and the results are much easier to interpret than integrating more-or-less discrete deformations at 100 locations. Win for small number of strain gages.
If you really want to record multiple contact positions (as shown in the set of photos on the website first page), then an array of point sensors is great, and yes/now is much easier to deal with than strain gage output. Win for large number of switches.
Within some limits, this dimpling technique offers the potential for having areas of higher/lower resolution (as a sensor) or curvature (as a deformation) by altering the size of the domes.

Not sure how small it could go but as long as the proportions (diameter, 'dome' displacement, material thickness) are maintained they should behave similarly. I worked mostly with .006 302 stainless but OBDs functioned the similarly in thicker 302.

Within minimum radius limits, as long as the material doesn't absorb flexural forces OBD behavior is very predictable. It might be ideal with AI to compare and learn switching patterns. There might be a lot of applications where high resolution is overkill, or remote sensing is unnecessary, expensive, or impractical.

There was some interest in it for auto seat sensors for air bag deployment for instance. It offered some advantages but they were well entrenched in thin film pressure sensors.

 

[Hightemp]

My family and friends have called me a crackpot. The videos were done with early low cost digital camera around the turn of the century.

I don't think using strain gauges could provide true 2D profile and you'd have a lot of analogue data to analyze trying to do it. An OBD sensor row or rows would give digital patterns made for AI pattern analysis. Low resolution, but also low cost with large scale applications.

Well, now that you show up, seeming reasonable, and not taking my comments too personally, I feel like a dick. So, thanks a lot!

 

[bistabledome]

Well, now that you show up, seeming reasonable, and not taking my comments too personally, I feel like a dick. So, thanks a lot!

No worries. I should have updated that stuff a long time ago.

 

[Bill D]

Reminds me of Slap Bands from the 80's.
Bill D