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4

Regarding point 1, yes you are understanding the problem correctly. Regarding points 1 and 2, I believe what you are looking for is the Nyquist-Shannon sampling theory. This theory says that your sampling frequency should be greater than 2x your "highest frequency of interest". This is to prevent aliasing, where you can incorrectly measure a high-...


3

Going forward, a Klann linkage has a near-vertical leg drop action. (See the legs at left in the wikipedia animated GIF.) It has a near-vertical leg lift action if running in reverse. (See the legs at right in the illustration.) Note, this linkage and some other leg mechanism linkages use a rotary crank; ie, rather than using a 180° back-and-forth motor, ...


2

One chooses different leg designs for different reasons. Sometimes there are specific design goals, involving the workspace, manipulability, and dynamics, but sometimes the designs are less intentional, with choices made for other reasons. Petman, the predecessor to the Atlas series was designed to mimic human kinematics for testing protective clothing. ...


2

From my side I can provide two remarks. First the human have elastic actuators (muscles) with a lots of sensors for balance. Whereas robots have mostly rigid actuators with a few dampers here and there to avoid breaking the motors on collision, and then they have far less sensing capabilities to maintain balance. So the two are not really comparable. Another ...


2

The linkages suggested by jwpat7 are great, and I would probably prefer to use something like that. But, if you want something really simple, then you might be able to get away with a four-bar linkage like this type of thing. Although it does depend on continuous rotation, so maybe not appropriate for your application. With a servo-motor that rotates back-...


2

In addition to the reasons given by Ugo, studying humanoid robots in general helps in the medical field too. Trying to understand what sensors/systems robots need helps us understand what sensors/systems we use If we can make a fully functioning humanoid robot, then individual parts such as an arm or a leg can be converted to a better functioning prosthetic ...


2

I would say: Compactness of the structure: imagine humanoid robots that are required to operate in household environment: two-legged robots might have less difficulties in navigating among tables and chairs standing very close each other. Energy consumption: of course the power needed increases proportionally with the number of legs. Human likeness: an ...


2

If you're only trying to walk forward the fitness function could be the distance covered by the biped. If you're also trying to control the heading, you could define a slightly more complex function which correlates the covered distance and the heading input.


1

Their page for the ATLAS robot states the joints are hydraulically activated. A number of their other big robots also use hydraulics. For example Big Dog uses a small motorbike/go-kart engine to run a hydraulic pump which drives cylinders. (Very high budget stuff for an individual developer to get into, I suspect.)


1

What you are asking is "why build something that is hard to make when there are easy to make solutions?" Simple answer: "because you learn more when you do something that is hard." Also if yu want a robot that can function in a world with humans then if is best if the robot is in the shape of a human. We have constructed out world based on our shape and ...


1

Really simple; Bipedal robots are designed to operate in environments made for ..... bipedal people. A swimming bipedal robot is probably not a good idea. Since climbing stairs, stepping over curbs, sitting in vehicles, opening doors and reaching into cabinets are all environment issues due to a design for humans, you can save a lot of contingency ...


1

Sentis' lab at UT Austin has open source code that implements many of the control topics mentioned in his thesis. You can check it out here: https://github.com/liangfok/controlit Specifically for the internal forces monitoring, you can checkout: https://github.com/liangfok/controlit/blob/b8f3ba056b5329e26b9519c8923c43ae58f0dcd9/controlit_core/include/...


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