Categories
3D Printing Industry

RIZE debuts the 2XC 3D printer – technical specifications and pricing

RIZE has launched its new RIZE 2XC 3D printer. The health and safety conscious desktop machine is aimed at professional designers and engineers looking to produce strong and durable composite parts with a vast range of materials. Dubbed an “adaptive workplace” printer, it is safe for use in both offices and homes – a welcome […]

Go to Source
Author: Kubi Sertoglu

Categories
3D Printing Industry

Functional airbag housing container produced via 3D printing with CRP Technology

Joyson Safety Systems (JSS), a Michigan-headquartered mobility safety specialist, has used SLS 3D printing with CRP Technology’s carbon reinforced composite material Windform SP to manufacture a functional airbag housing container prototype. Looking to explore the potential of additive manufacturing in its production processes, the JSS Core innovations team sought to manufacture a functional Driver Airbag […]

Go to Source
Author: Anas Essop

Categories
3D Printing Industry

NIOSH publishes health & safety advice for 3D printing with filaments and metal powders

The National Institute for Occupational Safety and Health (NIOSH) has published two new posters regarding 3D printing material safety for the workplace and at home. The first details steps that can be taken to ensure safe FDM operation with filaments and the second is concerned with metal powder handling. The information compiled in the posters is […]

Go to Source
Author: Kubi Sertoglu

Categories
3D Printing Industry

Würth signs agreement with Markforged to distribute 3D printers

Würth, the German distributor of fasteners, MRO and safety equipment, has signed a deal with Markforged, the US manufacturers of composite and metal 3D printers, to sell 3D printers to its customers in North America.  The deal will allow Würth to provide Markforged 3D printers to its customers in the general manufacturing market, as well […]

Go to Source
Author: Paul Hanaphy

Categories
3D Printing Industry

UL publishes independent study on 3D printed polymer properties

Global safety certification company, UL, has published an independent study on the effects of 3D printing on polymer properties. The results of the study have been used to develop a framework to qualify materials for safety-critical industrial components. The Illinois-based company hopes the framework will aid individuals and companies across the AM supply chain in […]

Go to Source
Author: Kubi Sertoglu

Categories
3D Printing Industry

UL and ASTM International sign agreement to publish AM facility safety standard

Underwriters Laboratories (UL), the safety consulting and certification firm, and global standards developer ASTM International have signed a memorandum of understanding (MoU) which will result in an ASTM-ISO standard for additive manufacturing facility safety management. Specifically, the MoU between UL and ASTM seeks to establish a framework for cooperation on developing an international, dual-logo ISO […]

Go to Source
Author: Anas Essop

Categories
ScienceDaily

‘Spillway’ for electrons could keep lithium metal batteries from catching fire

Nanoengineers at the University of California San Diego developed a safety feature that prevents lithium metal batteries from rapidly heating up and catching fire in case of an internal short circuit.

The team made a clever tweak to the part of the battery called the separator, which serves as a barrier between the anode and cathode, so that it slows down the flow of energy (and thus heat) that builds up inside the battery when it short circuits.

The researchers, led by UC San Diego nanoengineering professor Ping Liu and his Ph.D. student Matthew Gonzalez, detail their work in a paper published in Advanced Materials.

“We’re not trying to stop battery failure from happening. We’re making it much safer so that when it does fail, the battery doesn’t catastrophically catch on fire or explode,” said Gonzalez, who is the paper’s first author.

Lithium metal batteries fail because of the growth of needle-like structures called dendrites on the anode after repeated charging. Over time, dendrites grow long enough to pierce through the separator and create a bridge between the anode and cathode, causing an internal short circuit. When that happens, the flow of electrons between the two electrodes gets out of control, causing the battery to instantly overheat and stop working.

The separator that the UC San Diego team developed essentially softens this blow. One side is covered by a thin, partially conductive web of carbon nanotubes that intercepts any dendrites that form. When a dendrite punctures the separator and hits this web, electrons now have a pathway through which they can slowly drain out rather than rush straight towards the cathode all at once.

Gonzalez compared the new battery separator to a spillway at a dam.

“When a dam starts to fail, a spillway is opened up to let some of the water trickle out in a controlled fashion so that when the dam does break and spill out, there’s not a lot of water left to cause a flood,” he said. “That’s the idea with our separator. We are draining out the charge much, much slower and prevent a ‘flood’ of electrons to the cathode. When a dendrite gets intercepted by the separator’s conductive layer, the battery can begin to self-discharge so that when the battery does short, there’s not enough energy left to be dangerous.”

Other battery research efforts focus on building separators out of materials that are strong enough to block dendrites from breaking through. But a problem with this approach is that it just prolongs the inevitable, Gonzalez said. These separators still need to have pores that let ions flow through in order for the battery to work. As a consequence, when the dendrites eventually make it through, the short circuit will be even worse.

Rather than block dendrites, the UC San Diego team sought to mitigate their effects.

In tests, lithium metal batteries equipped with the new separator showed signs of gradual failure over 20 to 30 cycles. Meanwhile, batteries with a normal (and slightly thicker) separator experienced abrupt failure in a single cycle.

“In a real use case scenario, you wouldn’t have any advance warning that the battery is going to fail. It could be fine one second, then catch on fire or short out completely the next. It’s unpredictable,” Gonzalez said. “But with our separator, you would get advance warning that the battery is getting a little bit worse, a little bit worse, a little bit worse, each time you charge it.”

While this study focused on lithium metal batteries, the researchers say the separator can also work in lithium ion and other battery chemistries. The team will be working on optimizing the separator for commercial use. A provisional patent has been filed by UC San Diego.

Go to Source
Author:

Categories
ScienceDaily

Advance in next-generation lithium metal batteries

A Washington State University research team has developed a way to address a major safety issue with lithium metal batteries — an innovation that could make high-energy batteries more viable for next-generation energy storage.

The researchers used a formulation for their batteries that led to the formation of a unique, protective layer around their lithium anode, protecting the batteries from degradation and allowing them to work longer under typical conditions. Led by Min-Kyu Song, assistant professor in the WSU School of Mechanical and Materials Engineering, the researchers report on the work in the journal, Nano Energy.

Lithium metal is considered the “dream material” for batteries, Song said. That’s because among known solid materials, it has the highest energy density, meaning that batteries could run twice as long and hold more energy than the ubiquitous lithium-ion batteries that power most modern-day electronics. While lithium-ion batteries work by passing lithium ions between a graphite anode and a lithium cobalt oxide cathode, the anode in a lithium-metal battery is made of the high-energy lithium metal.

“If we can directly use lithium metal, we can improve the energy density of batteries dramatically,” Song said.

While the advantages of lithium metal have been known for decades, researchers have never been able to make them work safely. As electrons travel between the anode and cathode through the external circuit to power a device, Christmas-tree like dendrites begin to form on the lithium metal. The dendrites grow until they cause electric shorts, fires, or explosions. Even if they don’t catch on fire, the lithium metal batteries also very rapidly lose their ability to charge.

The WSU research team developed a battery in which they packed selenium disulfide, a non-toxic chemical used in dandruff shampoo, into a porous carbon structure for their cathode. They added two additives to the liquid electrolytes that are typically explored in next-generation lithium batteries.

The two additives worked synergistically and formed a protective layer on the lithium metal surface that was dense, conductive, and robust enough to suppress the growth of dendrites while allowing good cycling stability, Song said. When tested at typical current densities people would use for electronics, the protected lithium metal anode was able to re-charge 500 times and retained high efficiency.

“Such a unique protective layer led to little morphological changes of the lithium anode over cycling and effectively mitigated the growth of lithium dendrites and unwanted side reactions,” he said.

The researchers believe their technology can be scalable and cost-effective.

“If commercialized, this novel formulation has real potential,” Song said. “Compared to solid-state batteries which are still years away, you don’t have to change the manufacturing procedures, and this would be applicable to real industry much sooner, opening up a promising route toward the development of high-energy lithium metal batteries with a long cycle life.”

The researchers are continuing to work on the battery, developing a separator that will further protect the battery materials from deterioration and enhance safety without compromising performance.

This work was supported by Washington State’s Joint Center for Deployment and Research in Earth Abundant Materials (JCDREAM).

Story Source:

Materials provided by Washington State University. Original written by Tina Hilding. Note: Content may be edited for style and length.

Go to Source
Author:

Categories
ScienceDaily

Who’s liable? The AV or the human driver?

A recent decision by the National Transpiration Safety Board (NTSB) on the March 2018 Uber crash that killed a pedestrian in Arizona split the blame among Uber, the company’s autonomous vehicle (AV), the safety driver in the vehicle, the victim, and the state of Arizona. With the advent of self-driving cars, the NTSB findings raise a number of questions about the uncertainty in today’s legal liability system. In an accident involving an AV and a human driver, who is liable? If both are liable, how should the accident loss be apportioned between them?

AVs remove people from the hands-on task of driving and thus pose a complex challenge to today’s accident tort law, which primarily punishes humans. Legal experts anticipate that, by programming driving algorithms, self-driving car manufacturers, including car designers, sensor vendors, software developers, car producers, and related parties who contribute to the design, manufacturing, and testing, will have a direct influence on traffic. While these algorithms make manufacturers indispensable actors, with their product’s liability potentially playing a critical role, policy makers have not yet devised a quantitative method to assign the loss between the self-driving car and the human driver.

To tackle this problem, researchers at Columbia Engineering and Columbia Law School have developed a joint fault-based liability rule that can be used to regulate both self-driving car manufacturers and human drivers. They propose a game-theoretic model that describes the strategic interactions among the law maker, the self-driving car manufacturer, the self-driving car, and human drivers, and examine how, as the market penetration of AVs increases, the liability rule should evolve.

Their findings are outlined in a new study to be presented on January 14 by Sharon Di, assistant professor of civil engineering and engineering mechanics, and Eric Talley, Isidor and Seville Sulzbacher Professor of Law, at the Transportation Research Board’s 99th Annual Meeting in Washington, D.C

While most current studies have focused on designing AVs’ driving algorithms in various scenarios to ensure traffic efficiency and safety, they have not explored human drivers’ behavioral adaptation to AVs. Di and Talley wondered about the “moral hazard” effect on humans, whether with exposure to more and more traffic encounters with AVs, people might be less inclined to exercise “due care” when faced with AVs on the road and drive in a more risky fashion.

“Human drivers perceive AVs as intelligent agents with the ability to adapt to more aggressive and potentially dangerous human driving behavior,” says Di, who is a member of Columbia’s Data Science Institute. “We found that human drivers may take advantage of this technology by driving carelessly and taking more risks, because they know that self-driving cars would be designed to drive more conservatively.”

The researchers used game theory to model a world with interacting players who try to select their own actions to optimize their own goals. The players — law makers, AV manufacturers, AVs, and human drivers — have different goals in the transportation ecosystem. Law makers want to regulate traffic with improved efficiency and safety, self-driving car manufacturers are profit-driven, and both self-driving cars and human drivers interact on public roads and seek to select the best driving strategies. To capture the complex interaction among all the players, the researchers applied game theory methods to see which strategy each player settles on, so that others will not take advantage of his or her decisions.

The hierarchical game helped the team to understand the human drivers’ moral hazard (how much risk drivers might decide to take on), the AV manufacturer’s impact on traffic safety, and the law maker’s adaptation to the new transportation ecosystem. They tested the game and its algorithm on a set of numerical examples, offering insights into behavioral evolution of AVs and HVs as the AV penetration rate increases and as cost or environment parameters vary.

The team found that an optimally designed liability policy is critical to help prevent human drivers from developing moral hazard and to assist the AV manufacturer with a tradeoff between traffic safety and production costs. Government subsidies to AV manufacturers for the reduction of production costs would greatly encourage manufacturers to produce AVs that outperform human drivers substantially and improve overall traffic safety and efficiency. Moreover, if AV manufacturers are not regulated in terms of AV technology specifications or are not properly subsidized, AV manufacturers tend to be purely profit-oriented and destructive to the overall traffic system.

“The tragic fatality in Arizona involving a self-driving automobile elicited tremendous attention from the public and policy makers about how to draw the lines of legal liability when AVs interact with human drivers, cyclists, and pedestrians,” Talley adds. “The emergence of AVs introduces a particularly thorny type of uncertainty into the status quo, and one that feeds back onto AV manufacturing and design. Legal liability for accidents between automobiles and pedestrians typically involves a complex calculus of comparative fault assessments for each of the aforementioned groups. The introduction of an autonomous vehicle can complicate matters further by adding other parties to the mix, such as the manufacturers of hardware and programmers of software. And insurance coverage distorts matters further by including third party stakeholders. We hope our analytical tools will assist AV policy-makers with their regulatory decisions, and in doing so, will help mitigate uncertainty in the existing regulatory environment around AV technologies.”

Di and Talley are now looking at multiple AV manufacturers that target different global markets with different technological specifications, making the development of legal rules even more complex.

“We know that human drivers will take more risks and develop moral hazard if they think their road environment has become safer,” Di notes. “It’s clear that an optimal liability rule design is crucial to improve social welfare and road safety with advanced transportation technologies.”

The study is titled “Liability Design for Autonomous Vehicles and Human-Driven Vehicles: A Hierarchical Game-Theoretic Approach.”

Go to Source
Author:

Categories
3D Printing Industry

RadTech publishes material handling health & safety poster for 3D printer resins

When considering safety in the operation of resin-based 3D printers it is important to note that the primary risk comes from exposure to uncured residues/materials. In keeping with good housekeeping procedures a major recommendation for 3D printing users is that 3D printers and the handling of uncured resins should be done in a well-ventilated area. […]

Go to Source
Author: Beau Jackson