3D Design with a Twist

3D Design with a Twist 3D Design with a Twist 3D Design with a TwistImagine a little robotic dinosaur that shrinks down small enough to fit through a gap at the bottom of a wall and then redeploys at full scale on the other side. Or, perhaps a curved claw that stretches out over a mound of rubble to save a teddybr bear trapped in a fire.Those are just some of the many possibilities for a new way of making collapsible devices based on curved telescoping parts. Think of them as the unexpected progeny of a pirates telescope and Marvel superhero Wolverines retractable claws.Computational methods help to determine what kinds of telescoping shapes are possible. Image Carnegie MellonTelescope entered the English language around 1650 as a noun to describe an optical instrument that magnifies distant objects. Once sailors began using easily stored telescopes, the noun became a verb to describe the linear extension of any set of nested cylinders into a longer object. Today, telescoping parts a re used in everything from camera tripods and antennas to baskets, and, of course, telescopes. Seeing Wolverines retractable claws at a Maker Faire inspired Keenan Crane and Stelian Coros to put a new twist on telescoping parts.The two are assistant professors of computer science and members of the Robotics Institute of Carnegie Mellon University. After seeing the claws retract, they began to wonder how many different types of objects they could make by using curved parts that bend and rotate as they telescope.It was an interesting moment for us, Crane says. The artist had figured out one way to do it, but we wanted to know all the possible ways you could possibly hope to do it.The answer, it turns out, is a lot. Any space curve of constant curvature can be a telescope, Crane says. Working with Christopher Yu, a doctoral candidate, Crane and Coros developed a way to automate the design of telescoping structures.Their mathematical model for telescoping structures started with a few a ssumptions Each shell must be manufacturable from rigid material such as metal it should extend and contract without bumping into itself and there should be no empty or wasted space between nested pieces.Their work on the model led to a key geometric insight. Both simple pirate telescopes and the most complicated telescoping objects can be defined by simple geometric curves that exhibit a constant amount of bend and one or more arbitrary twists.Crane likens that to a clump of instant ramen. All the noodles curl and bend by roughly the same amount, but they all twist in lots of different ways. This accounts for their bountiful variety of shapes.They tested the model by simulating a metal salamander-like lizard that collapses into a package that looks something like a complex gear box. Other simulations included the shrinking dinosaur and teddy-bear-saving claw.They also prototyped several structures using a 3-D printer, including a flexible robotic arm and a hard-surfaced tent that e xpands to several times its original volume. Telescoping structures also expand the production capacity of 3-D printers. You can print a much bigger structure than your normal 3-D printer would allow, because when you take it out, it deploys to a greater volume, Crane says.With so many possibilities, Crane and Coros are looking for collaborators with ideas about how to control these devices. Because, thanks to their simulations, it does not take a telescope to see that potential applications are closer than ever. For Further DiscussionThe artist had figured out one way to do it, but we wanted to know all the possible ways you could possibly hope to do it.Prof. Keenan Crane, Carnegie Mellon University

Study Dietary changes led to humans pronouncing the f and v sounds

Study Dietary changes led to humans pronouncing the f and v soundsStudy Dietary changes led to humans pronouncing the f and v soundsApparently, labiodental sounds are a relatively recent evolutionary development.Labiodental constants are sounds that require the use of both the lip and upperteeth to produce, sounds like f and v for instance.Follow Ladders on FlipboardFollow Ladders magazines on Flipboard covering Happiness, Productivity, Job Satisfaction, Neuroscience, and moreAccording to the author of a new study, these phonetics were not achievable for our early-early ancestors.We can say with fairly good confidence that 20,000 or 100,000 years ago, these sounds just simply didnt exist, said linguistBalthasar Bickel,one of the authors.The cultural impact on biologyEven more intriguing than this, is the reason behind our ability to make certain sounds. The study states that changes in diet developed the human bite as they got older, enabling them to make certain noises, more specifi cally noises produced by utilizing the top teeth and lower lip found in about half of the languages spoken around the world.The jaw structure required to make labiodental constants were much less prevalent in the Paleolithic Period by reason of the rough diet that was strenuous on the teeth. The gradual switch to softer agricultural foods put less stress on teeth and jaws leading to overbites more frequently. Bringing the upper teeth and lower lip closer in proximity may have authored the Fuhsound for instance.We looked into the distribution of labiodental sounds across thousands of languages and their relation to the characteristic sources of food of the people speaking those languages, Bickel explained at a recent press conference.The linguistic researchers tested their postulation via biomechanics models. Their experiments determined that it takes 29% less muscular effort to form labiodental sounds when the speaker has an overbite.The findings indicate that the probability of pro ducing labiodental sounds increases slightly over time, and that means that some languages are likely to acquire them but not all languages will, says co-author Steven Moran.Contrary to the wisdom presented by the uniformity principle ( inthe absence of compelling evidence to the contrary, assume language to be uniform, with variety restricted to easily detectable properties of utterances) this new theory suggests that language has significantly changed over the last millenniums. Foods like corn wheat and rice, are less diverse and much easier on the teeth. The researchers behind the recent study found that hunter and gatherer societies used labiodentals about one third less than agricultural societies.The notion that cultural factors influenced biological developments is beyond fascinating.You might also enjoyNew neuroscience reveals 4 rituals that will make you happyStrangers know your social class in the first seven words you say, study finds10 lessons from Benjamin Franklins dai ly schedule that will double your productivityThe worst mistakes you can make in an interview, according to 12 CEOs10 habits of mentally strong people

Conduct your Next Interview as if it were the First

Conduct your Next Interview as if it were the FirstConduct your Next Interview as if it were the FirstConduct your Next Interview as if it were the First RossheimYour small geschftliches miteinander has achieved the revenue level where you can and must hire your next employee. Candidates are coming this afternoon for the interview. Are you ready to make one of the most important decisions of the year?Heres whatyou do look around your business, review your interview questionsandmake sure your new hireprovides a worthy return on investment just likeyour first hire did.Devote sufficient time to conduct and prepare for interviews. You know from experience (perhaps both positive and negative) that hiring decisions are among the most significant that you make. So allocate proportionate time to the process, especially for interviewing.Its important to slow down, says Bruce Bachenheimer, professor of management at Pace University. Small business owners are typically dealing with a myriad of critical issues and many are in a rush to hire. Consider using an interview guidefor better hiring.Learn the details of the open position. You cant know all the tasks that your people perform everyday unless you ask. Ask the person currently in the role their daily schedule, says Jason Carney of WorkSmart Systems, a professional employer organization.Know the specific duties and responsibilities of the open position, and be familiar with the job role and how it contributes to the overall business.Know the candidate before you shake hands. Its simple You wont win over the best candidates unless you prove that youre interested in their careers. Thoroughly research the candidate, says Sandra Lewis, of Worldwide 101, a virtual assistant service.Ive been part of many interviews where the interviewer got confused about who the interviewee was they got the background wrong or asked a question obviously geared towards someone else.Ask broad questions to prompt candidates to reveal them selves. Begin by asking the opposite of yes-no questions. Ask generic, open-ended questions and see how they answer, says attorney Jonathan Broder, owner of Strategic Professional Staffing.How they respond and what they decide to share with you will reveal a lot about how they think and who they are.Ask detailed questions to assess expertise. After youve gotten the candidate to reveal himself or herself, drill down to assess subject-matter expertise and analytical skills with more specific interview questions. You might even bring in a current employee in a similar role to help evaluate her or his prospective peer.Find out what the candidate knows about your small business. Whether from the local newspaper or your web site or public records, theres a lot that a candidate can and therefore should find out about your business before coming to speak with you. Candidates level of knowledge is a good indicator both of their genuine interest in your trade and their research abilities. T ake this opportunity to test them.Pose a question regarding an issue your company has recently confronted.Maybe youve had a customer servicesnafu. Or a human resources issue. Or a cash-flow glitch. Lay out the situation and ask the candidate how they would go about resolving it.Suit the questions to the job and your companys culture. Your small company culture is water, and you are the fish who is so immersed that you cant even see it. But you ignore whats invisible at your peril.Ask two types of questions, says Angelo Kinicki , a professor of management at the W. P. Carey School of Business at Arizona State University.The first type should be behavioral interview questions that assess if the candidate has the knowledge, skills, and competence to do the job. The second kind of question should focus on person-culture fit.Observe their communication style. You may have seen it happen An otherwise competent hire starts work at a small business and a wave of misunderstandings begets a f lut of mishaps. Nows your chance to try to head off such trouble.Have the candidate join a staff discussion, react to a difficult test situation, engage in a discussion on an issue important to the team over a casual lunch, says Bachenheimer. Carefully observe body language, temper, congeniality and other traits not just oral communications.Keep the interview legal. While youre doing all this productive probing, take care to keep the discussion professional at all times. If a question feels too personal and intrusive, it probably is, says Broder, who is an attorney.To ensure you dont expose yourself to legal liability, stick to questions that pertain only to the candidates job history, experience, education and skills. Many ill-advised hiring managers ask about how the candidates home life will affect availability for work this can be illegal as well as unethical. Inform yourself and be sure you follow a legal hiring process.