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Updated: 30 min 43 sec ago

better way of publication

Thu, 2018-02-01 14:52

In reply to Some ideas for a possible new journal

Then I am confused.  I still do not understand what is better


1) is it cheaper?   But the little money given to editors for hard work, and for typesetters to improve papers, although a small part of the big margin Elsevier and other companies make, is needed to ensure high quality


2) is it faster?  Most journals are fast these days


3) do I get a more proper peer review?   Why?  Most journals even of high reputation, have troubles to find high quality reviewers, and I know many scientists of even high level (not perhaps of high ethical standards) who review papers in few seconds, saying this is wrong, because I did it much better 2 years ago.


So please recap which one is better.

Thank you!

Thu, 2018-02-01 14:38

In reply to Great job, Christoph!

Dear Zhigang:  Thank you for your positive comment -- this means a lot to me and my students!


Our work on HASEL artificial muscles synergizes different areas I have studied during my PhD and postdoc, and our papers benefit from all the things I have learned from my academic advisors. My ambitious aim when starting my own lab in Boulder was to invent a new class of artificial muscles that enables a next-generation of soft robots that are high-speed, versatile and electrically powered, thereby avoiding the issues that arise from the use of compressors and valves in soft pneumatic actuators:

1) I have started to appreciate the wide range of possible geometries of soft fluidic actuators when working as a postdoc with George Whitesides at Harvard. Using liquid dielectrics as a hydraulic fluid, HASEL actuators inherit the versatility of soft fluidic actuators.

2) Even before I started my PhD with Siegfried Bauer, he introduced me to the fascinating world of dielectric elastomer actuators (DEAs). I was immediately convinced that this type of actuator is extremely promising, when seeing the speed, efficiency and ability to capacitively self-sense deformation. Just like dielectric elastomer actuators, HASEL artificial muscles are driven by Maxwell stress, and thus inherit the high-performance and the capacitive self-sensing abilities of DEAs. In contrast to DEAs, HASELs use a liquid dielectric, which self-heals after dielectric breakdown, and thus avoid central issues of DEAs, such as catastrophic dielectric breakdown and electrical aging. For this exact reason, industry widely uses liquid dielectrics in HV transformers.

3) Zhigang, when working together with you as a postdoc, I have started to realize that the nonlinearities and instabilities in soft active materials are a feature, and not a problem. Donut HASELs undergo a safe electromechanical instability to reach large deformations. I am absolutely certain that the mechanics community will very soon find new types of electromechanical instabilities in various designs of HASEL actuators. Additionally, HASEL actuators benefit from the unique properties of stretchable, transparent ionic conductors, a topic we introduced together in 2013.


GEO, standing for Gel, Oil, and Elastomer is without a doubt an incredibly interesting combination of materials, that might have applications far beyond the field of soft actuators. I am looking forward to seeing what the Suo group comes up with in this area! My lab has been working on HASEL actuators since more than two years, and we had central results ready more than a year ago. It is always a gamble when aiming to publish in top journals such as Science or Nature, as these outlets require top quality stories, figures, videos and writing -- all of which takes a lot of time and increases the chances that other groups publish the idea first. I am incredibly proud of my team of first-rate students, who pushed the initial papers introducing HASELs over the finish line with creativity, dedication and hard work. 4 of them -- Eric Acome, Nicholas Kellaris, Timothy Morrissey, Shane K. Mitchell -- have helped me put together the journal club post and will be discussing with us here.

When thinking about industrial applications of HASEL artificial muscles, we realized that the fundamental principles do not depend on elastomers and conductive gels. In our Science Robotics paper on Peano-HASEL actuators, we introduce a materials system with thin polymer films and evaporated metal layers. This materials system is amendable to large scale industrial fabrication, and it does not depend on highly stretchable elastomers or conductive gels. Depending on the specific application, HASELs can be built from a wide variety of different materials.


Zhigang, thank you for your question on liquid dielectrics. While being widely used in the high voltage industry, there is a surprisingly small number of academic papers available on the topic of self-healing in liquid dielectrics. A while back I wanted to better understand the fundamentals of dielectric breakdown and looked for good literature; initially I focused on solid dielectrics, but then found work from the Research Laboratory of Electronics (RLE) at MIT that opened my eyes about the benefits of liquid dielectrics and the rich physics of electrical breakdown: "Mechanisms Behind Positive Streamers and Their Distinct Propagation Modes in Transformer Oil" by Professor Markus Zahn and colleagues. Here is a link:



HASEL actuators solve important issues, but they open up just as many new questions, challenges and opportunities. In our journal club post, we mention a few areas we look forward to working on together with the mechanics, materials, and robotics communities!


Very Inspiring Idea

Thu, 2018-02-01 14:10

In reply to Some ideas for a possible new journal

This is a very interesting idea. Mechanical engineering and mechanics is a very closed door discipline compared to computer science. It will not be an exaggeration to say that the whole open source movement is at the forefront of the rapid progress of computer science. 

Mike, original post was to

Thu, 2018-02-01 14:04

In reply to Some ideas for a possible new journal

Mike, original post was to seek suggestions from the community to come up with a better way of publication. cdmHUB has not implemented my ideas yet. Currently it can serve as a Composites arXiv with review capability. It expose you to a focused community with the possibility to provide feedback on the same site, comparing to arXiv. Researchers in some fields do take arXiv seriously. Somebody paid serious attention to award Grigori Perelman a Fields Medal. 

I have difficulty to see the connection of reviewing your paper with my original suggested ideas. 

Biswajit, composites can

Thu, 2018-02-01 13:50

In reply to Re: Composite fatigue paper

Biswajit, composites can fatigue and we are working a project entitled multiscale fatigue damage of composites right now. Composite fatigue life is much longer than metals though for many applications, that might cause the conclusion that composites do not fatigue. 

Dear Biswajit, Thanks a lot

Thu, 2018-02-01 13:47

In reply to Re: cdmHUB speed

Dear Biswajit, Thanks a lot for your feedback. We are in the process to move cdmHUB to AWS, hoping it will be faster internationally. We did not notice its slowing down at home in US. 


Re: Composite fatigue paper

Thu, 2018-02-01 13:39

In reply to speaking of composite materials,...

I started posting papers on arXiv in the early 2000s but have found that not too many mechanics people read arXiv papers (or cite them).  That's probably because of lack of awareness.  A dedicated server for mechanics papers would help a bit (people have to search in condensed matter physics/mathematics/computer science on arxiv for mechanics papers).

I've heard many "experts" on composites in NZ say that there is no fatigue in polymer composites.  Maybe that's why you don't get reviewers?   Or you may have annoyed a few people and will have to wait until they retire?

-- Biswajit

Re: cdmHUB speed

Thu, 2018-02-01 13:33

In reply to I agree that more important

It's been a while, but I recall that the website took a while to load.  The scalability is determined by the capacity of the server to accept a large number of users simultaneously and the efficiency of the server side software.  I can access most commercial sites worldwide at high speeds.  It's academic sites that turn out to have speed bottlenecks.  On the positive side, I can at least access your site; unlike the Luxembourg (Bordas) site. iMechanica is also relatively slow.

-- Biswajit


but why would I want to get additional reviews if later I go

Thu, 2018-02-01 13:22

In reply to Some ideas for a possible new journal

for a proper journal?

Just today, I finished a big review paper with 35 or so authors which took us endless discussions and even personal attacks -- it was extremely difficult task.   One of the authors was extremely agressive and made 12 pages of "internal review" which took us ages to answer and converge, DESPITE the external standard reviewer asked only for MINOR review.

So in my case, why would I want to submit to your system, if the paper is already on ArXiv for everyone to see it --- but nobody takes it for serious unless is peer reviewed?  Why would I send it to your other system which supposedly makes peer review, and how you convince reviewers to work for a non high reputation journal?

I get dozens of emails a day to review papers from low class journals, which I don't even reply to. 

If you want your system to provide external reviews for people to improve their papers, then ArXiv is good enough.  I can share it to many places, like I did already, and people usually read it, and few of them comment to me.

Yes, I was hoping to make instead another experiment:  if you could review that particular paper on imechanica for me, and see if anybody takes this discussion for serious.  I promise you, it is a good experiment, because the paper is quite critical and you will have hard time to find good reviewers, who make good reviews.

But I am sure you don't want to avoid this "test" --- try!

Wonderful work!

Thu, 2018-02-01 13:21

In reply to Journal Club for February 2018: HASEL artificial muscles for high-speed, electrically powered, self-healing soft robots

Hi, Christoph, Thanks for such a wonderful and inspiring work.

Naturally, muscle contains water and can self-heal. Previous artificial muscle (DEA) mimics functions of muscle, but suffers from electric breakdown. Whereas synthesizing self-healing dielectric elastomer could be an awkward alternative for common mechanical engineers, using liquid dielectric to engender self-healing ability for artificial muscle is simple yet effective. This is really a brilliant work.

The opportunities and challenges section is already very comprehensive, and will lead to many follow-up researches across multiple disciplines.

One particular issue about the practical usage of this device: the hydrogel electrodes are exposed. This may cause several challenges: 1. Whereas hydrogels can retain water with dissolved hygroscopic salts, the water content fluctuates with the ambient humidity. Does the fluctuation of water content (i.e. resistance) of hydrogels affect the device performance? 2. The hydrogel electrodes may contact with other materials, and short circuit might happen if the materials are conductive. 3. Using hydrogel makes the overall device transparent. But the device cannot work in water environment.  Have you found potential solution for this issue?


Thank you.

Yes, you can send it to a

Thu, 2018-02-01 13:08

In reply to Some ideas for a possible new journal

Yes, you can send it to a proper journal later and you only give us the rights to display it (like what you did with arXiv). I can invite experts in composite fatige damage to review your paper. Others who have a cdmHUB account can also review it. The review comments are public.

You signup a free account, then, click Resources->Contribute, select Publications. then you follow the rest of the steps, by putting title, abstracts, and tags, then upload the pdf as an attachment. My admin will approve your submission.

Can you tell me what you want to achieve with your experiment? To see whether somebody would like to review your paper and give you some feedback for improving the paper so that you can make it ready for journal publication or to test whether I can get somebody to review your paper anonyously? 

Nice work!

Thu, 2018-02-01 12:50

In reply to Journal Club for February 2018: HASEL artificial muscles for high-speed, electrically powered, self-healing soft robots

Really impressive work! Christoph. I am very enjoying reading, but still have some questions.

1. When the actuator lift weights, the part composed of elastomer membrane and soft electrode is stretchable, does that compromise the actuation?

2.The voltage applied determines how heavy the weight can lift. But for lifting heavy weight, your voltage is very high, does that hinder the practical application? 

3. When the elastomer membrane contacts, does the high voltage cause electric breakdown of the elastomer?

4. What is the maximum liquid you can put in the actuator? Is there any limitation? 

Thank you, and again really appreciate your idea!

but if I upload on, do I get peer review?

Thu, 2018-02-01 12:41

In reply to Some ideas for a possible new journal

And later I can also send it to a proper journal?   And people would see the reviews of my papers, or only I could do it?  

Please explain step by step --- not everybody understand:  at least, I don't.

Anyway, I see you don't want to make my experiment.  I was hoping it would attract attention.

Actually, if you upload your

Thu, 2018-02-01 11:56

In reply to Some ideas for a possible new journal

Actually, if you upload your paper on as a publication, users can perform anonymously directly. Cut and paste is something for computers, it is not good use of an editor's time :)

you collect the reviews, and then cut and paste!

Thu, 2018-02-01 11:20

In reply to Some ideas for a possible new journal

it is so simple, like editors do!

Good luck in your endeavour

Thu, 2018-02-01 10:58

In reply to Thanks, Emilio.  I will try

Good luck in your endeavour Wenbin, it is a very good idea and I will try to do my best to support it.

Regarding sharing. I very actively share my manuscripts on as many platforms as possible (arXiv, repositories, ResearchGate, etc.). Our institutions may have access to all the journals that we are interested in but we need to think about those with fewer resources and make sure they can follow and contribute to scientific progress. In Europe, all research must be open access by 2020. This is typically done through institutional repositories (green open access model) after the journals' embargo period. Implying that, if willing to wait 12-24 months, one could have access to all papers without subscription and independently of other resources (Sci-Hub, ResearchGate, arXiv, etc.). When I started doing research I did most of my literature reviews by searching keywords in Web of Science or Scopus. I see that all the PhD students do it now in Google Scholar, where all the versions of the manuscript can be easily found (repositories, arXiv, even ResearchGate and the like).

Great job, Christoph!

Thu, 2018-02-01 10:54

In reply to Journal Club for February 2018: HASEL artificial muscles for high-speed, electrically powered, self-healing soft robots

Dear Christoph:  Fantastic work! Heartiest congratulations on the publication of two spatacular papers!  

Several members in the group at Harvard and in China had elements of the idea, but have not pushed so far and so powerfully as you have done.  We had a name for an ongoing outline:  GEO, standing for Gel, Elastomer, and Oil. 

Here is a paper titled organic liquid-crystal devices based on ionic conductors.  We encountered the combination of the three materials, GEO, in our experimental setup, commented on some interesting attributes more basic than the liquid crystal devices, and did a rudimentary theoretical analysis in the supplementary information (Fig. S4).

The students here at Harvard and in China are all your admirers.  Me, too.  May the field that you help initiate engage more researchers, inspire deep scientific questions, and open new applications. 

A technical question.  Have you found good reference on self-healing of transformer oil?  This is really a neat idea.

Is the staggeringly profitable business of scientific publishing

Wed, 2018-01-31 18:14

In reply to Some ideas for a possible new journal

If you are a real entrepeneur, maybe you are the next Robert Maxwell, forget about academia:  all academics of the world are somehow naive people who all worked for a single man and his huge profits.   Maybe you will be the next one....   If this is your idea, and you want to abandon academia, then I am interested :)

It is an industry like no other, with profit margins to rival Google – and it was created by one of Britain’s most notorious tycoons: Robert Maxwell. By Stephen Buranyi


I agree that more important

Wed, 2018-01-31 17:14

In reply to Some ideas for a possible new journal

I agree that more important is sociology. Change that is hard and it requires those who are already estalished and do not have to chase after those things you mentioned to try better publication models if we truly believe such models exist. 

Regarding the speed of cdmHUB, does it take too long to load the web pages, or is it too slow to run simulation codes remotely? The speed is mainly related with the internet speed. We are constantly improving the site, your more specific inputs will be helpful. I have used cdmHUB to conduct workshops in Italy before with 20+ students in a classroom fighting for wifi, I do notice that the speed goes down. The scalablity of the technology is (or at least should be) determined by the internet speed at the user end. 

Re: New journal etc.

Wed, 2018-01-31 16:54

In reply to Some ideas for a possible new journal

There are two aspects to a journal: the technology and the sociology (and their associated costs). 

Hosting a journal (e.g., on Amazon Web Services - S3) carries a cost that is a function of the number of users and downloads.  That cost can be a complex nonlinear function and needs to be computed using reasonable assumptions.  I've found that is too slow to use from my location in NZ and I'm not sure how scalable the technology is.  However, the technology is the easy part.

More important is the sociology.  Academic publication is tied to reputations, grants, promotions etc. in Academia.  Unless that changes I don't see the need for another journal in Mechanics.  On the other hand, a preprint server could go a long way towards rapid dissemination of ideas.  Because most people accept new ideas only after someone they respect has adopted the idea (of if the idea is so compelling and has so much adoption that they don't have a choice), I think even a preprint server for mechanics (and general engineering) will need a lot of marketing to gain acceptance.  I see that as at least a 10 year process.

-- Biswajit


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