If we abolish patents innovation will finally be possible.
There is a patent for a 3D printer enclosed in a box. A number of plastics print much better when in an enclosure with no drafts and more easily controllable temperatures.
But instead, 3D printers must be sold and function on their own without a box, to avoid the patent. Enclosures are then sold separately and you end up with a 3D printer in an enclosure anyway, but that doesn’t infringe on the patent… so it’s allowed.
I assume you are talking about this Stratasys patent that expired earlier this year, https://patents.google.com/patent/US6722872
> 1. A three-dimensional modeling apparatus comprising a heated build chamber in which three-dimensional objects are built, a base located in the build chamber, a dispensing head for dispensing modeling material onto the base, the dispensing head having a modeling material dispensing outlet inside of the build chamber, and an x-y-z gantry coupled to the dispensing head and to the base for generating relative movement in three-dimensions between the dispensing head and the base, characterized in that: the x-y-z gantry is located external to the build chamber and is separated from the chamber by a deformable thermal insulator. [...]
There is progress. Japan has been developing assistance exoskeletons as an answer to elder care problems: power assist devices to allow not-strong people to lift/carry elderly people. Interestingly, much development has gone into pneumatic devices as they are inherently more waterproof than electric.
"In Japan, the commercialization of exoskeletons is already underway. Innophys, a startup founded in 2013 at the Tokyo University of Science, has already dispatched about 1,000 units across the country, in particular to Asahi-Sun, an elderly care supplier. Lighter than ActiveLink's AWN-03, Innophys' Exo-Muscle is a little less quick but offers more flexibility for a similar lifting capacity of 22 to 30 kilos (48 to 66 pounds). But Exo-Muscle uses an entirely different technology: compressed air, which is injected into rubber valves that inflate and contract."
https://worldcrunch.com/tech-science/an-aging-japan-turns-to...
Innophys suit has a compressed-air tank with limited endurance, built to be periodically refilled from a stationary compressed-air system on job sites (since those are common in many industrial settings). Notably, their ad copy says: "Simply fill it with air using the supplied pump and it is ready for use. Therefore it can be used anytime, anywhere, for an unlimited amount of time, easily. When the assistive power weakens, just add more air." i.e. you're expected to be able to pump the thing (they include a hand pump as a last resort!) at any time.
The AWN-03, for its part has one set of high-power motors for when it's connected to AC power and a lower-power motor for battery operation; that Panasonic division, in the 5 years since that story was written, discontinued that product and defined down the problem to less power-hungry assist modes, namely short assistance during particularly strenuous motions.
To be clear (not to be snide, just to improve clarity), increased power density is the ability to discharge energy in larger amounts in shorter time periods (think heavy lift olympians). Energy density is the ability to store large amounts of energy for longer periods of time (think long distance runner). Some applications, like cell phones are quite happy with high energy density, but relatively low power density. Others, like an battery-electric drill, need more power density but can offset the low energy density by swapping out batteries and having a rotable pull.
Great idealic batteries for this application would have both large energy and power desnity. I say this because people often overlook "batteries" that people don't refer to ass batteries because they generally don't come in a self-contained cell (they have subsystems that don't benefit much from cellular architectures). Case in point are Hydrogen fuel cells. I'm not saying their better than Li-ion, but they are for certain applications. Often H2 fuel cells are paired with Li-ion batteries or supper capacitors to provide improved power when transient energy bursts are needed. H2 fuel is stored in some tank - perhaps a pressure tank, perhaps in the form of Aluminum and water reaction, or for this application it may likely be some metal hydride that stores H2 'benignly'. However, to your point, even these metal hydrides have a lot of room and potential for improving energy density.
My only point here is that, cureently, the best answer may not be a single cellular battery, but some hybriid of energy storage technologies.
It's possible to have the device be corded and stay within a room or set of rooms.
Is wheeling the verb for it anyway?