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Otherlab Working on a 'Fundamental Jump' in Technology for Exoskeletons (Video)
"Otherlab," says their projects page, "is a private Research and Development company with a number of core competencies. We welcome industrial partnerships and commercialization partners. We have worked with dozens of companies globally from small start-ups to multi-nationals and Fortune 500 businesses. We develop enabling new technologies through an emphasis on prototyping coupled to rigorous physics simulation and mathematical models. We develop our own design tools because it's lonely at the frontier and to create new things and ideas, you often have to create the tools to design them." | One of their projects is building low-cost, inflatable exoskeletons that can be used as prosthetics or -- one presumes -- as strength multipliers for people who have working limbs. This is the project today's interviewee, Tim Swift, is working on. (Alternate Video Link)
Another marketing press release!
I guess that we don't get enough of this at trade shows anymore!
Do not look into laser with remaining eye.
Batteries are heavy. It takes an awful lot of energy to even give someone human strength, not counting the additional costs to carry the battery and the exoskeleton itself.
As such, all exoskeletons suits currently in development either are tethered to a wall plug or have a ridiculously low battery capacity.
A couple of people tried to make it work using fuel powered engines (gasoline, etc.) to power the , but those are also heavy once again resulting in shortened times between re-fueling.
Even if you eliminate the dead weight of human limbs, (ie. small pack bots) the operating time is too short for things
Anyone that makes a significant improvement in this area would not portray it as "working exoskeleton", but instead as "INCREDIBLY LONG LIFE BATTERY/GENERATOR".
excitingthingstodo.blogspot.com
Are you nuts? This is going to help my mom to walk. Screw military applications—if they can make this work, it will change the lives of a lot of people who have physical disabilities.
Missed it by that much Tim said Swiftly.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
a power source that isn't crappy. That would enable exoskeletons and robots that are useful.
If you watch the demo videos, they all either have a power cord dangling off the exoskeleton/robot (presumably plugged into A/C mains) or an annoyingly loud and smoky 2-stroke generator running onboard. That's because current batteries provide nowhere near enough juice to power these suits/robots to any degree of usefulness.
We aren't lacking in servo/microcontroller/robotics tech, we're lacking a decent battery tech.
The big reason why pneumatics aren't used as much in robotics is that air is very compressible, which leads to all sorts of nastiness when you make pneumatic actuators.
Because air is compressible, compressing air is not very efficient compared to say hydraulics. This is bad for exoskeletons.
The other problem is that the compressibility of air limits the 'bandwidth,' or how fast these actuators can actuate and un-actuate controllably, achievable with these actuators. In addition, the bandwidth of pneumatic actuators is often below the frequency of human walking, making them impractical most exoskeleton applications.
And of course, there's more to it than compressibility at play here that could make these actuators impractical. Since these actuators use a rubber membrane, these actuators are subject to hysteresis, significant temperature effects, and creep.
Rubber, when stretched and unstretched quickly, heats up causing the rubber to change it's stiffness. In addition, the temperature of the rubber can also change due the air being pumped into them. Rubber, and other elastomers, also experiences a phenomenon known as creep, where it slowly stretches out with time. In fact, current industrial pneumatic muscles NEVER actuate exactly the same because of all this, and one has to use interesting control approaches.
I am also skeptical that this will be cheaper in practice than mass produced electric actuators. While the actuators themselves are cheap, the valves and other hardware necessary to control them are not. The actuators themselves will certainly wear out sooner than electric actuators(>10 years continuous operation for robot arm actuators) due to the creep mentioned above. With lower efficiency and increased maintenance costs the overall cost of using these could very well be higher.
In fact, the brushless motor in the compressor they show in the video probably can provide" 25% of the power of a normal human elbow," and the only reason it can't be used on a human elbow is that much of that power is at high-speed with low torque. If someone were to develop a compact and efficient gearbox for turning high speed- low torque into low speed-high torque, then one could mass produce it and skip all the pneumatic silliness.(Or just do what that company that robotics google just bought did and use watercooling/overclocking)
Pneumatics is way better exactly because air is compressible, that allows you to make something more akin to a controlled force actuator - making it easy to modulate force to pick up an egg or crush a brick. The actuators are also compliant, (inherently springy), meaning less precise positional control is required to do real world dynamic activities, and less energy will be required for things like walking/running. The control problem is mostly about modulating pressure quickly.
Rubber creep is obviously not a problem because the bladders are contained by a textile shell that doesn't creep. They provide an impermeable membrane to hold air in, not strength.
The big cost in conventional actuators is making an articulated structure that they can be attached to, and then all of the positional sensors and with tonnes of degrees of freedom that can accommodate a freely moving human body. If this can be built into suits then those costs and weights might be avoidable.
This approach would probably not make sense for industrial robotics or other precision applications. But exoskeleton/mobile robotics that have to interact with the real world could really benefit, particularly for exoskeletons where the human provides the fine control. Obviously a long way to go with development, but worth exploring.