
Marine Corps Shelves Futuristic Robo-Mule Due to Noise Concerns - bgraves
http://www.military.com/daily-news/2015/12/22/marine-corps-shelves-futuristic-robo-mule-due-to-noise-concerns.html
======
jt2190
For those who don't understand the U.S. military funding process: This is
being shelved because there isn't money to continue work, not because of a
fundamental problem with the technology. [1] It's more of a "We'd LOVE to give
you this cool thing... Too bad we don't have any money to work on it. Oh
well!"

[1] The article mentions that they built a quieter version of the robot that
carried less. More interesting were problems about how to maintain the things
(from training mechanics to supplying replacement parts) and how to integrate
them into current training. (How/when to use? Advantages? Disadvantages?)

[2] For those of you interested in the U.S. Military's use of Mules in more
recent times: [http://www.newyorker.com/magazine/2010/02/15/riding-
high](http://www.newyorker.com/magazine/2010/02/15/riding-high)

~~~
Animats
BigDog's power pack was originally a constant speed gasoline engine driving a
hydraulic pump and an electrical generator. That's the noisy engine in the
earlier videos. The LS3 was supposed to have a new, quieter power pack
developed with a small variable-speed Diesel engine. That was subcontracted
out by Boston Dynamics. This is as good as it ever got: [1] It still sounds
like a dirt bike.

The hydraulic system used is very controllable but not particularly efficient.
There's no energy recovery and no springyness; it's brute-force hydraulics.
That was reasonable for an experimental machine, but not acceptable in the
production product. Atlas, the BD humanoid, has the same problem. It's too
similar to BigDog, and weighs about 330 pounds. Schaft, Google's other
humanoid robotics company, uses water-cooled electric motors, like Tesla. You
can enormously overload electric motors for a few seconds without hurting
them, and if you have cooling and temperature monitoring, that works fine.
This is probably the way forward for anything smaller than a pony.

[1]
[https://www.youtube.com/watch?v=arIJm2lAfR8](https://www.youtube.com/watch?v=arIJm2lAfR8)

~~~
grogenaut
One big drawback not called out to electric is you have to power it to have it
hold still. Hydraulic can just leave a valve closed which may or may not
require power.

Then again just have it "sit". This may not be the best tactically though in
small group engagements as "sit" is movement and freeze is dead stop.

I'll let people who know more about that debate it though.

~~~
jonmrodriguez
> you have to power it to have it hold still

Is it common to work around this by supplementing the electric motor with a
disc brake?

Depending where you want to be on the tradeoff between complexity vs energy-
efficiency, you could use a hydraulically-powered disc brake in order for the
brake to not need power except during state transitions.

~~~
grogenaut
Thought about this for a bit. I'm betting it's used. The deal with brakes is
the ratio of the friction applicable by the brake and the lever distance of
the compared to the lever arm it's stopping. I'm watching a movie so I'm not
going to do the math right now but I think the size of disc rotor you could
get on say a mule's knee joint versus the lever arm length of say a lower leg
might cause problems either with the size of the rotor.

My thinking is mountain bike discs are 120mm/4.8"-203mm/8" diameter compared
to a 29" wheel.

These are meant to stop a 160lb person who is going down a hill. Well Slow to
a stop not lock dead in place as the wheel would break free so it's not the
full stopping power of a real.

Anyway my gut reaction is it might be difficult in this use case. I think a 8"
rotor on a similar lever arm might have trouble fully locking down that joint
and would be very large and flimsy (8" thin sheet of metal) for rugged use.
Plausible though.

But hey I failed out of mechanical engineering into computer science for a
reason so maybe I shouldn't be trusted :)

~~~
LeifCarrotson
Many robotics applications use ballscrew linear actuators. These contain a
cage of ball bearings in a spiral around a ball screw, and they move a given
distance for each revolution. You can apply a braking force to the ball screw,
which will have a large mechanical advantage over trying to brake against the
joint itself.

~~~
grogenaut
Very true. My cnc uses these. However I couldn't see getting it to walk or hop
like these mules. You don't really get impulse with a ballscrew.

------
Lambdanaut
These are the "Big Dog" mules being built by Boston Dynamics, who was recently
acquired by Google.

Google has been against militarizing the robots since acquisition, so they're
no doubt happy to have this contract dropped.

To be clear, this doesn't mean the project is shelved, it means the contract
with the Marine Corps is shelved. Google will be able to focus more directly
on civilian uses for the mules from here on out.

~~~
melling
Why are they against militarizing robots? It pays the bills. They could start
with consumers or business but it's harder to build a market. This makes it
harder to fund further development.

Once the technology is developed by anyone for non-military use, transitioning
to the military is easy. There's not some magic that prevents consumer
developed technology from reaching the battlefield.

~~~
ceejayoz
> Why are they against militarizing robots? It pays the bills.

Because money isn't everything?

> There's not some magic that prevents consumer developed technology from
> reaching the battlefield.

That doesn't mean you're required to actively help it along.

~~~
walshemj
Google is based on the internet which came out of DOD research

~~~
sitkack
And the nature of DoD research back then was more generally applicable to
things besides killing. The Mansfield Amendment is what turned ARPA into DARPA
and pushed to curtail pure research. If you couldn't kill someone with it, it
wouldn't get funded.

    
    
        The Mansfield Amendment of 1973 expressly limited 
        appropriations for defense research (through ARPA/DARPA) 
        only to projects with direct military application. 
        Some[who?] contend that the amendment devastated American 
        science, since ARPA/DARPA was a major funding source for 
        basic science projects of the time; the National Science 
        Foundation never made up the difference as expected.
    
            https://en.wikipedia.org/wiki/DARPA#Later_history

------
homerowilson
There are these things called "mules." They're quiet, can carry about 200lbs.,
and can refuel themselves as they go by eating grass and drinking water...

~~~
lmm
The logistics of keeping them fed and watered, having trained handlers, and
treating them for injuries are nontrivial. And they're prone to unhelpful
reactions in a firefight. There are good reasons they've largely been
displaced by motor vehicles. Combining the go-anywhere ability of legged
propulsion with the advantages of motor transport seems like a good enough
idea to merit study.

~~~
JabavuAdams
Much easier than the logistics of keeping a robot operational in the field.
You don't care whether the Taliban captures your flesh and blood mule, but you
really don't want them capturing your world's-most-advanced robotic mule.

~~~
kiba
The Taliban are not going to have the capability to reverse engineer and
produce their own copy, let along having the logistic capability of keeping it
in the field.

~~~
dredmorbius
But the parties they sell it to, for substantial combat-enabling cash, will.

------
jarmitage
Can anyone in robotics weigh in on whether new approaches like pneubotics /
otherlab [0, 1] make Boston Dynamics' super heavy/noisy/expensive robots
irrelevant or not? That's what Saul Griffith has been saying at least [2], I'd
like to hear an impartial take on it

[0] [http://www.pneubotics.com/](http://www.pneubotics.com/)

[1] [https://otherlab.com/projects](https://otherlab.com/projects)

[2] "[...] we're the only game in town." 21:00 onwards
[https://youtu.be/gyMowPAJwqo?t=1263](https://youtu.be/gyMowPAJwqo?t=1263)

~~~
pj_mukh
Boston Dynamics' primary innovation is in the software/control design. The
reason their robots are noisy is because they really haven't innovated a whole
lot in the basic actuator design. That's not to say their mechanical design
was easy, not by a long shot. It's super impressive stuff!

Any new inventions that would make their mechanical design steer away from
loud hydraulics would no doubt be amazing. However, without Boston dynamics'
delightfully ground-breaking controls software design, it'll be dead in the
water!

For a little bit of proof, see who they are hiring!
[http://www.bostondynamics.com/bd_jobs.html](http://www.bostondynamics.com/bd_jobs.html)

~~~
PhasmaFelis
A lot (most?) of the noise comes from the engine, not the hydraulics, and the
engine can't be replaced because sufficiently high-capacity batteries do not
exist yet. That's not a problem that can be solved by innovative actuators.

~~~
pj_mukh
That too. Also engine design was contracted out.

------
wehadfun
why do they need this. What are they carrying? Are marines supposed to go
without resupplies for weeks/months where they would need an additional robot
mule to carry everything?

~~~
arethuza
I found this interesting article:

[http://www.nationaldefensemagazine.org/archive/2013/march/pa...](http://www.nationaldefensemagazine.org/archive/2013/march/pages/marinecorpsstruggleswithsea-
basedsupplylines.aspx)

Which includes this quote:

 _" “What we’ve seen is that when Marines come ashore, they’re carrying 130
pounds of food, water, batteries, ammo, you name it, on their backs because
fundamentally, they don’t trust sea-based logistics to keep them supplied,”_

~~~
ZanyProgrammer
Which is ironic __, because since World War 2 the Marines basically function
as a de facto Army, and enjoy all the benefits of American global air and sea
superiority.

Really, as a former soldier myself, the ideal solution is to stop having
soldiers and Marines carrying so much damn gear. Much, much easier said than
done.

*By ironic I mean "silly ass Marines"

------
thinkcontext
I wonder at what price point the civilian market could support these? There
must be a fair number of applications for resupply where humans (sherpas),
actual animal mules or helicopters are required, ie, forestry, National Park
rangers, science, recreation, etc.

~~~
davidw
> forestry, National Park rangers

In most areas where these guys operate, actual mules are probably cheaper, and
can be refueled with locally available forage. Not to mention they're more
suitable for that kind of environment.

Perhaps more 'extreme' environments where that forage is not available would
be more suitable?

~~~
grogenaut
Walking the wonderland trail a few years ago I was remarking to my friend that
in some of the most remote meadows at the top (7-8k feet)
([https://www.google.com/maps/@46.9181125,-121.7649511,731m/da...](https://www.google.com/maps/@46.9181125,-121.7649511,731m/data=!3m1!1e3))
of the trail there were long stretches of very nice chat trails. He was saying
what a pain it would be to bring the chat up and was trying to decide if it
was ATVs or mules or whatever. I guessed helicopter.

We asked a ranger at the bottom. Answer: Helicopter. "They just dangle a huge
bag of chat and we cut a hole and walk it along the path letting it pour out.
Those mountain meadows are easier to do than the steep stuff at the bottom"

~~~
Gracana
I figured "chat" was gravel or something from the context, but had never heard
the term before. Maybe I'm the lone idiot, but in case anyone else is
confused:

"Chat is a term for fragments of siliceous rock, limestone, and dolomite waste
rejected in the lead-zinc milling operations that accompanied lead-zinc mining
in the first half of the 20th century. [...] Although poisonous, chat can be
used to improve traction on snow-covered roads; as gravel; and as construction
aggregate, principally for railroad ballast, highway construction, and
concrete production."

[https://en.wikipedia.org/wiki/Chat_%28mining%29](https://en.wikipedia.org/wiki/Chat_%28mining%29)

~~~
grogenaut
In general it just means small crushed gravel. It's usually white or tan. Not
sure if it's always a remnant from mining or not. Does a good job on the trail
though.

------
hoodoof
Government probably gets better bang for its buck by mounting a pistol onto
each of 1,000 flying drones that only cost $300 per unit. That's an army I'd
be unenthused about facing.

~~~
melted
Except the ones made by their contractors would be $30k apiece for the same
thing.

------
justinator
I'm having a hard time seeing why you couldn't take something like a fat bike,
and put an electrical assist motor on it, and have troops use that, mostly by
pushing it. If you run out of battery, it still works 100% except now you have
to push all the weight (or pedal, which could also be used to charge the
battery). Gotta leave in a hurry? Use the bike, or just throw it away. Slash
the tires and it's pretty much useless for the enemy.

Probably < $1,000 wholesale in off the shelf parts. Def. less than $40mm.
Easily carry 100lbs of gear.

~~~
rtkwe
Even a bike like that works only on a limited amount of terrain. Add the 100
ish pounds of weight they need to be able to carry in addition to a person and
they get bogged down even worse. The ways you can pack them is also really
limited because soldiers would need to be able to take everything off and
carry it still in the even that it does get bogged down.

~~~
justinator
> Even a bike like that works only on a limited amount of terrain.

Same as this monstrosity. Except it's $39,999,000 cheaper.

Bicycle infantry units have been, and are now a Thing.

------
analog31
I wonder if the robot actually works better than a power assisted wagon or
wheelbarrow, perhaps with caterpillar tracks instead of wheels.

------
ck2
Irony of it being all electric motors/actuators but needing a gas engine to
power it so it is very loud.

~~~
gene-h
If it is like the original big dog then it doesn't use electric
motors/actuators it uses hydraulics that are driven by the gas engine.[0]
Supposedly it gets ~0.5 miles per gallon.

[0]
[http://www.bostondynamics.com/img/BigDog_Overview.pdf](http://www.bostondynamics.com/img/BigDog_Overview.pdf)

------
kpauburn
As a submarine veteran, noise is bad.

------
deathhand
These will be turned into mounted auto targeting gun platforms if they haven't
been already. This is the 2nd time reading about this topic so the DOD PR team
is in full spin. This might be a intelligence counter-measure to show the
world 'see we dont want to use this tech!' when in reality it has been taken
over into black ops world.

------
tdy721
I call B.S. A nuclear powered one would probably be pretty quiet.

~~~
jkldotio
Are Rat Things[0] really viable?

"MMRTG contains a total of 10.6 pounds (4.8 kilograms) of plutonium dioxide
(including Pu-238) that initially provides approximately 2,000 watts of
thermal power and 110 watts of electrical power when exposed to deep space
environments."[1]

Even if ~110 watts per ~4.8 kilograms is good for legs in agile situations, as
opposed to wheels in a slow-and-steady rover, losing one in combat means
you've just given the enemy a few kilos of radioactive material.

[0][https://en.wikipedia.org/wiki/Snow_Crash#Rat_Things](https://en.wikipedia.org/wiki/Snow_Crash#Rat_Things)
[1][http://mars.nasa.gov/msl/files/mep/MMRTG_FactSheet_update_10...](http://mars.nasa.gov/msl/files/mep/MMRTG_FactSheet_update_10-2-13.pdf)

------
outside1234
is it range anxiety that drives using a gas motor versus battery pack and
solar panels?

~~~
varjag
It takes more energy per mile for a walker versus a car, so apparently
batteries are ruled out so far.

Solar is not an option in practical transportation. The energy yield per
surface area is way too low.

~~~
orionblastar
So then no AT-AT or AT-ST walkers because of the same problems. Better stick
to tanks instead.

~~~
varjag
Tanks are not exactly solar or battery driven either, am not quite sure what
is your point.

------
superkuh
They should've gone with hydrogen peroxide based monopropellant linear
actuators.

