mechanical engineering (7)

Dr. Lonnie Johnson...

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Lonnie Johnson holds his patent for the pump-action water gun he developed, now known as the Super Soaker

Topics: African Americans, Black History Month, Diversity in Science, Mechanical Engineering, NASA, Nuclear Engineering, STEM

Engineer Lonnie Johnson invented the massively popular Super Soaker water gun and is developing a thermoelectric device to convert solar energy into sustainable power.

Lonnie Johnson invented the Super Soaker in 1989 and has since dedicated his engineering skills to creating more efficient rechargeable batteries and sustainable solar power. As a child, Johnson learned to build toys from his father and was later inspired to make a career of his early talent by fellow Black inventor George Washington Carver. Since the debut of Johnson’s famous toy, hundreds of millions of Super Soakers have been sold, and the water gun was added to the National Toy Hall of Fame in 2015. Seven years later, Johnson was inducted into the National Inventors Hall of Fame. Today, in addition to working on batteries, the inventor and his team are developing the Johnson Thermoelectric Energy Converter (JTEC), an engine that converts heat from solar energy into electricity more effectively than current technology.

Lonnie George Johnson was born on October 6, 1949, in Mobile, Alabama. His father was a World War II veteran who worked as a civilian driver at nearby Air Force bases, while his mother worked in a laundry and as a nurse’s aid. During the summers, both of Johnson’s parents also picked cotton on his grandfather’s farm.

Out of both interest and economic necessity, Johnson’s father was a skilled handyman who taught his six children to build their own toys. When Johnson was still a small boy, he and his dad built a pressurized chinaberry shooter out of bamboo shoots. At age 13, Johnson attached a lawnmower engine to a go-kart he built from junkyard scraps and raced it along the highway until the police pulled him over.

Out of both interest and economic necessity, Johnson’s father was a skilled handyman who taught his six children to build their own toys. When Johnson was still a small boy, he and his dad built a pressurized chinaberry shooter out of bamboo shoots. At age 13, Johnson attached a lawnmower engine to a go-kart he built from junkyard scraps and raced it along the highway until the police pulled him over.

Growing up in Mobile in the days of legal segregation, Johnson attended Williamson High School, an all-Black facility, where he was told not to aspire beyond a career as a technician despite his precocious intelligence and creativity. Nevertheless, inspired by the story of famed African American inventor George Washington Carver, Johnson persevered in his dream of becoming an inventor.

Nicknamed “The Professor” by his high school buddies, Johnson represented his school at a 1968 science fair sponsored by the Junior Engineering Technical Society (JETS). The fair took place at the University of Alabama at Tuscaloosa, where, just five years earlier, Governor George Wallace had tried to prevent two Black students from enrolling at the school by standing in the doorway of the auditorium.

The only Black student in the competition, Johnson debuted a compressed-air-powered robot, called “the Linex,” which he had painstakingly built from junkyard scraps over a year. Much to the chagrin of the university officials, Johnson won first prize. “The only thing anybody from the university said to us during the entire competition,” Johnson later recalled, “was ‘Goodbye’ and ‘Y’all drive safe, now.’”

After graduating with Williamson’s last segregated class in 1969, Johnson attended Tuskegee Institute (today Tuskegee University) on a scholarship. He earned a bachelor’s degree in mechanical engineering in 1973, and two years later, he received a master’s degree in nuclear engineering from the school.

After Johnson received his degrees, he joined the U.S. Air Force and became an important member of the government's scientific establishment. He was assigned to the Strategic Air Command, where he helped develop the stealth bomber program. Johnson moved on to NASA’s Jet Propulsion Laboratory in 1979, working as a systems engineer for the Galileo mission to Jupiter and the Cassini mission to Saturn, before returning to the Air Force in 1982.

Despite his busy days, Johnson continued to pursue his [own] inventions in his spare time. One of his longtime pet projects was an environmentally friendly heat pump that used water instead of Freon. Johnson finally completed a prototype one night in 1982 and decided to test it in his bathroom. He aimed the nozzle into his bathtub, pulled the lever, and blasted a powerful stream of water straight into the tub. Johnson’s instantaneous and instinctive reaction, since shared by millions of kids around the world, was pure delight.

In 1989, after another seven years of tinkering and tireless sales-pitching, during which he left the Air Force to go into business for himself, Johnson finally sold his device to the Larami Corporation. The “Power Drencher” initially failed to make much of a commercial impact, but after additional marketing efforts and a name change, the “Super Soaker” became a massively successful item. It topped $200 million in sales in 1991 and went on to annually rank among the world’s top 20 best-selling toys.

Dr. Lonnie G. Johnson, Biography dot com

 

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Agibot vs Optimus...

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The firm is reported to have produced at least 962 humanoid robots so far. Global Times/Agibot

Topics: Applied Physics, Artificial Intelligence, Electrical Engineering, Mechanical Engineering, Robotics

The company has established a “data collection factory” to gather real-world data through activities like folding clothes and doing laundry.

A Chinese robotics firm has started mass-producing humanoid robots for general use, while its US counterparts, like Tesla, are aiming for such a feat in 2026.

Agibot, or Zhiyuan Robotics, showcased footage of its manufacturing facility on its official website and revealed that it’s on course to produce 1,000 units by the end of the year, according to a Chinese online news outlet.

Founded in February 2023 by Peng Zhihui, a former participant in Huawei’s “Genius Youth” program, the Shanghai-based startup launched its first humanoid robot model, the Raise A1, in August 2023.

On August 18, the company introduced five new wheeled and bipedal humanoid robot models designed for various tasks, including domestic chores and industrial work.

First Law:
A robot may not injure a human being or, through inaction, allow a human being to come to harm.

Second Law:
A robot must obey the orders given it by human beings except where such orders would conflict with the First Law.

Third Law:
A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.

Isaac Asimov, "I, Robot."

China’s Agibot eyes 1,000-strong humanoid robot army to beat Elon Musk’s Optimus, Jijo Malayil, Interesting Engineering

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Fast Charger...

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Significant Li plating capacity from Si anode. a, Li discharge profile in a battery of Li/graphite–Li5.5PS4.5Cl1.5 (LPSCl1.5)–LGPS–LPSCl1.5–SiG at current density 0.2 mA cm–2 at room temperature. Note that SiG was made by mixing Si and graphite in one composite layer. Inset shows the schematic illustration of stages 1–3 based on SEM and EDS mapping, which illustrate the unique Li–Si anode evolution in solid-state batteries observed experimentally in Figs. 1 and 2. b, FIB–SEM images of the SiG anode at different discharge states (i), (ii), and (iii) corresponding to points 1–3 in a, respectively. c, SEM–EDS mapping of (i), (ii), and (iii), corresponding to SEM images in b, where carbon signal (C) is derived from graphite, oxygen (O) and nitrogen (N) signals are from Li metal reaction with air and fluorine (F) is from the PTFE binder. d, Discharge profile of battery with cell construction Li-1M LiPF6 in EC/DMC–SiG. Schematics illustrate typical Si anode evolution in liquid-electrolyte batteries. e, FIB–SEM image (i) of SiG anode following discharge in the liquid-electrolyte battery shown in d; zoomed-in image (ii). Credit: Nature Materials (2024). DOI: 10.1038/s41563-023-01722-x

Topics: Applied Physics, Battery, Chemistry, Climate Change, Electrical Engineering, Mechanical Engineering

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new lithium metal battery that can be charged and discharged at least 6,000 times—more than any other pouch battery cell—and can be recharged in a matter of minutes.

The research not only describes a new way to make solid-state batteries with a lithium metal anode but also offers a new understanding of the materials used for these potentially revolutionary batteries.

The research is published in Nature Materials.

"Lithium metal anode batteries are considered the holy grail of batteries because they have ten times the capacity of commercial graphite anodes and could drastically increase the driving distance of electric vehicles," said Xin Li, Associate Professor of Materials Science at SEAS and senior author of the paper. "Our research is an important step toward more practical solid-state batteries for industrial and commercial applications."

One of the biggest challenges in the design of these batteries is the formation of dendrites on the surface of the anode. These structures grow like roots into the electrolyte and pierce the barrier separating the anode and cathode, causing the battery to short or even catch fire.

These dendrites form when lithium ions move from the cathode to the anode during charging, attaching to the surface of the anode in a process called plating. Plating on the anode creates an uneven, non-homogeneous surface, like plaque on teeth, and allows dendrites to take root. When discharged, that plaque-like coating needs to be stripped from the anode, and when plating is uneven, the stripping process can be slow and result in potholes that induce even more uneven plating in the next charge.

Solid-state battery design charges in minutes and lasts for thousands of cycles, Leah Burrows, Harvard John A. Paulson School of Engineering and Applied Sciences, Tech Xplore

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As The Worm Turns...

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Schematic diagram of the worm-inspired robot. Credit: Jin et al.

Topics: Applied Physics, Biomimetics, Instrumentation, Mechanical Engineering, Robotics

Bio-inspired robots, robotic systems that emulate the appearance, movements, and/or functions of specific biological systems, could help to tackle real-world problems more efficiently and reliably. Over the past two decades, roboticists have introduced a growing number of these robots, some of which draw inspiration from fruit flies, worms, and other small organisms.

Researchers at China University of Petroleum (East China) recently developed a worm-inspired robot with a body structure that is based on the oriental paper-folding art of origami. This robotic system, introduced in Bioinspiration & Biomimetics, is based on actuators that respond to magnetic forces, compressing and bending its body to replicate the movements of worms.

"Soft robotics is a promising field that our research group has been paying a lot of attention to," Jianlin Liu, one of the researchers who developed the robot, told Tech Xplore. "While reviewing the existing research literature in the field, we found that bionic robots, such as worm-inspired robots, were a topic worth exploring. We thus set out to fabricate a worm-like origami robot based on the existing literature. After designing and reviewing several different structures, we chose to focus on a specific knitting pattern for our robot."

A worm-inspired robot based on an origami structure and magnetic actuators, Ingrid Fadelli, Tech Xplore

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Like Mushrooms for Plastics...

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Credit: VTT Technical Research Centre of Finland

Topics: Biology, Biotechnology, Chemistry, Materials Science, Mechanical Engineering

A research group from VTT Technical Research Center of Finland has unlocked the secret behind the extraordinary mechanical properties and ultra-light weight of certain fungi. The complex architectural design of mushrooms could be mimicked and used to create new materials to replace plastics. The research results were published on February 22, 2023, in Science Advances.

VTT's research shows for the first time the complex structural, chemical, and mechanical features adapted throughout the course of evolution by Hoof mushroom (Fomes fomentarius). These features interplay synergistically to create a completely new class of high-performance materials.

Research findings can be used as a source of inspiration to grow from the bottom up the next generation of mechanically robust and lightweight, sustainable materials for various applications under laboratory conditions. These include impact-resistant implants, sports equipment, body armor, and exoskeletons for aircraft, electronics, or windshield surface coatings.

Mushrooms could help replace plastics in new high-performance ultra-light materials, VTT Technical Research Centre of Finland, Phys.org.

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LCE...

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The microfiber actuators on the metal mesh collector (top left), under SEM (bottom left), under heat activation (top right), and integrated into an artificial arm (bottom right). | Credit: Qiguang He et al./Science Robotics

Topics: Materials Science, Mechanical Engineering, Nanotechnology, Robotics

A new artificial fiber spun from a polymer called liquid crystal elastomer (LCE) using high-voltage electricity replicates the strength, responsiveness, and power density of human muscle fibers, scientists report. When powered by heat or near-infrared light, the fibers pulled upward and downward or oscillated back and forth.

"Our work may open up an avenue to build soft robotics or soft machines using liquid crystal elastomers as the actuator," the authors write in their paper, published in the August 25 issue of Science Robotics.

When applied to a variety of potential applications, the fiber actuators successfully controlled the pinching motion of a micro-tweezer, directed the movement of a microswimmer and a tiny artificial arm, and pumped fluids into a light-powered microfluidic pump.

Inspired by the utility of tiny fibers in nature, scientists sought to create artificial fibers that could also serve as ubiquitous tools in robotics, as sensors or assistive devices, for example. In the past few years, researchers succeeded in constructing fiber actuators driven by heat or light that are as strong and flexible as natural fibers. However, many of these artificial threads respond to their stimulus very slowly, due to their large size or complex actuation processes. When fibers can respond quickly, there's a trade-off in size or quality; for example, micro-yarns made of carbon nanotubes are fast actuators but aren't as strong as other fibers.

"Animal muscle fiber exhibits superior mechanical properties and actuation performance," said senior author Shengqiang Cai, associate professor of mechanical and aerospace engineering at the University of California, San Diego. "Only a few existing materials show similar actuation behaviors as animal muscle, and the fabrication of fibers from those materials with a size and quality comparable to muscle fiber is not easy."

Electrically Spun Artificial Fibers Match Performance of Human Muscle Fibers, Juwon Song, American Association for the Advancement of Science

 

 

 

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Quadrupedal Robots...

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Image Source: Link below

Topics: Autonomous Vehicles, Mechanical Engineering, Research, Robotics

Abstract

Legged locomotion can extend the operational domain of robots to some of the most challenging environments on Earth. However, conventional controllers for legged locomotion are based on elaborate state machines that explicitly trigger the execution of motion primitives and reflexes. These designs have increased in complexity but fallen short of the generality and robustness of animal locomotion. Here, we present a robust controller for blind quadrupedal locomotion in challenging natural environments. Our approach incorporates proprioceptive feedback in locomotion control and demonstrates zero-shot generalization from simulation to natural environments. The controller is trained by reinforcement learning in simulation. The controller is driven by a neural network policy that acts on a stream of proprioceptive signals. The controller retains its robustness under conditions that were never encountered during training: deformable terrains such as mud and snow, dynamic footholds such as rubble, and overground impediments such as thick vegetation and gushing water. The presented work indicates that robust locomotion in natural environments can be achieved by training in simple domains.

Learning quadrupedal locomotion over challenging terrain, Joonho Lee1, Jemin Hwangbo 1,2, Lorenz Wellhausen1, Vladlen Koltun3, and Marco Hutter1

Science Robotics  21 Oct 2020:
Vol. 5, Issue 47, eabc5986
DOI: 10.1126/scirobotics.abc5986

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