Retractable caster wheel frame

Working on a podium - client is requesting a set of retractable casters so with the step on a single lever they are pulled up into base, lowering it to rest on it's own pedestal. A second step on lever lowers the wheels, essentially lifting podium up for transport. Idea is to keep casters hidden at all times and have a single pedal to actuate all 4 in unison.
I know I've seen a framed system that does this, as well as my client, but having a tough time locating. All I'm finding are single wheels, in which all 4 must be individually triggered. Likely I'm just not using the right trigger words for web search, but words such as frame, system, set and unison are of no luck so far.
Any direction for resources would be greatly appreciated.

Jeff

Jeff
shopsmith has a casters that work in pairs that does what you want.. you can find used ones on ebay..
Gary

Something like this? Its home made. Skip ahead to about the 9:30 mark

https://www.youtube.com/watch?v=_dGNyc1kHAw

If you put non rotating casters on the back edge (inside the structure to hide it) the podium can be tilted backwards slightly and wheel barreled wherever you want. I have used this method on podiums, pulpits and ambos when clients wanted maneuverability. It is rock solid and reliable and requires little engineering and experimentation.

Thanks for all the responses - good suggestions.
The Shopsmith looks pretty good, though a bit tall to tuck under as well as rigging a way to sync all 4. The setup in the Youtube video looks solid, but difficult to adapt a foot lever. While I agree with wayne's sense of simplicity and practicality, my client is uber particular. First request they had was for motorized.:rolleyes:

So far, it looks to me like the ridgid table saw base I found in an internet search under images looks perfect. One lever, all 4 casters, low profile, pretty simple. Problem is, you just cannot buy a kit to do this. Here's an image from someone's web documentation of assembling a Ridgid R4512 table saw base:

Attachment 31310

I did look at ereplacement parts, and found a part number for this entire assembly. Unfortunately, looks like it has since been reduced to a 3 caster system, and the parts vendor popped up with a message indicating this part was extremely rarely requested, and indicated some research on their end may be required to verify availability.

Still, hope someone may have run across a universal kit, as grim as the prospects appear at this point. Otherwise, I may look to having my brother (metal fabricator) quote a custom system based on this Ridgid system, which seems reasonably simple, if you follow general laws of physics. Just hate to kill a budget with excessive research.
Final punt may be simply to get a brake foot to keep it still. Client says they have "leaners" who will prop themselves against this podium as they speak.

jeff

Note that a 4 wheeled podium is also apt to be top heavy and tilt over unexpectedly when they hit a bump like a threshold.
If it goes over on the wrong person you could easily get sued.

Here is another idea. Maybe 2 wheels at a time?


https://www.youtube.com/watch?v=AmGirrDI3jU

Grizzly also has a mobile machine base, two fixed casters and two swivel casters on a adjustable sizw base.. they call it BEAR CRAWL... Gary..