Active Disassembly
Encyclopedia
Outline
Smart materials such as shape memory alloyShape memory alloy
A shape-memory alloy is an alloy that "remembers" its original, cold-forged shape: returning the pre-deformed shape by heating. This material is a lightweight, solid-state alternative to conventional actuators such as hydraulic, pneumatic, and motor-based systems...
s (SMA) are now offering the possibility of allowing complex items to be disassembled easily and in a potentially cost-effective manner. Other smart materials employed by AD include, shape memory polymers (SMP), smart layers, sprays, engineering polymers etc. The development of this technology could make recycling
Recycling
Recycling is processing used materials into new products to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, reduce energy usage, reduce air pollution and water pollution by reducing the need for "conventional" waste disposal, and lower greenhouse...
of consumer products more common and thus serve to be environmentally
Natural environment
The natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species....
friendly.
Eco-design and legislative background
Companies designing and manufacturing a range of consumer goods are becoming increasingly subject to legislative and other pressures requiring them to consider the "End of Life" (EoL) implications of their products. The ELV (End of Life Vehicle) Directive in Europe, for example, states that the current reuse and recycling level of 75% (by weight) has to be raised to 85% by 2015. The WEEE (Waste Electrical and Electronic Equipment) Directive is aimed at the eradication of landfill as a means of disposing of hazardous materials such as arsenic in LEDs. Manufacturers are also required to build strategies for disassembly into the design of their products. In the past designing products such as cars rarely involved consideration of what would happen when they were scrapped, although some companies, such as BMWBMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...
have been pro-active in this respect.
Research
Dr. Joseph Chiodo is the inventor of AD and ADSM technology. He focused his research on thermally triggered disassembly using shape memory materials. He set up a company called, "Active Disassembly Research" (ADR), which carries out its own research as well as working on behalf of other companies to develop and patent methods that can be used. His work first started in recycling related design solutions since the late 1980s. In 1991, his MA thesis investigated Design for Disassembly providing incentive for a new automated approach to what was at the time, a cumbersome endeavour. He started conducted experiments on alternatives from crude force to highly tuned approaches including temperature, vibration, volume, explosive, chemical and bio triggered dematerialization.Since then, this work has expanded to a variety of dematerialization technology including expanded triggering mechanisms, varied hierarchical control parameters, increased temperature allowances amongst other considerations including the aforementioned. Dr. Joseph Chiodo invented hundreds of AD, ADSM and other automated technology mechanisms since his initial inventions over 2 decades ago. His recent work includes specific component isolation and clean segregation of specific elements for re-use. In 1996, he conducted experiments on using typical engineering polymers such as PEEK, ABS, PC, Nylon and others; manipulating their shape memory properties for potentially more cost effective alternatives. This work has been re-addressed by H.Hussein, Dr. Mark Allen and Dr. David Harrison in a paper published in 2009 with results from collaborative work between Dr. Chiodo, Motorola, Nokia, Sony, Gaiker, Indumetal, IKP etc. but has so far produced only pre-competitive results.
From 1998, this field has gained an increased popularity by industry which has led to more extensive research. Dr. Jones has conducted work on ELVs amongst a variety of other novel approaches to AD using electrically triggered SMA mechanisms. Dr. Jones and Dr. Chiodo have recently developed a SMA NiTi releasing mechanism for LCD panels for clean and non-destructive dismantling of their macro assemblies' for desktop and laptop displays. It consists of an automated electrically triggered fine wire that lies dormant until triggered at EoL.
Dr. Jones has developed a group of applications for the ELV market. These include SMA devices for airbags, SMP devices for glass removal and a novel velcro releasing mechanism.
Dr. Neubert explored the field of active disassembly further by looking at other trigger methods to initiate disassembly. His conceptual ideas to use the volume increase of frozen water to disconnect certain parts of a product or to use soluble fasteners, are described in his dissertation published in 2000.
Barbara Willems elaborated on this research by focusing on the "pressure cells" described by Neubert. She developed a mathematical model to determine the optimal shape and dimensions of a pressure-activated fastener. Implemented in a product, these snap-fit-like fasteners enable dismantling through variations in ambient pressure. Since pressure variations are very unlikely to occur during the normal life-time of an electrical product, this trigger mechanism offers a more secure way of disassembly compared to temperature based triggering.
In Japan, U.S.A. and EU, various research departments in universities have investigated various strands of the technology. While there remains to be any mass produced and implemented applications of the technology in industry, work continues to this end. There has also been some work by various companies listed on the AD website.
Dr. Joseph Chiodo continues to invent a wide variety of active separation techniques. Besides employing smart materials, he also uses interstitial layers, smart adhesives, sprays, engineering polymers, bio-degradable components and other novel AD disassembly techniques. Many of these technological approaches are currently being developed to significantly reduce the environmental impact in electronic products. In fact, in 2009; ADR Ltd., the inventor's company has created the world's first active disassembly circuit board. By Christmas 2009, Dr. Chiodo published patents on LCD recycling, Indium isolation and related Active Disassembly technology.
Re-Manufacturing Research with AD
Dr. Ijomah has been investigating the application of AD technology applying it to the re-manufacturing of electronic products. To date, the work has been conducted with Dr. Chiodo with some papers on the topic in various journals.Advantages of AD
Most consumer products consist of a large number of parts and a wide range of materials. Disassembly at the end of a product's useful life is an inevitably complex and time consuming operation to ensure effective separation of all component parts for subsequent re-use or recycling. AD techniques permit the automation or semi-automation of this process and thus make it more viable. The incorporation of AD and the implications of companies taking responsibility for the end of life recycling of their products will have long term cost implications for the consumer.Hurdles of AD
There are currently significant obstacles preventing this technology to succeeding in the mass market. (cost, re-training, fin-cap/law-cap, arbitrage, legislative practice....to be continued.The use of smart materials
A wide range of methods are being developed for use in AD. These methods generally require the use of smart materialSmart material
Smart materials or designed materials are materials that have one or more properties that can be significantly changed in a controlled fashion by external stimuli, such as stress, temperature, moisture, pH, electric or magnetic fields....
s which respond to a stimulus in order to change shape or size and thus facilitate the release of parts. The materials involved include shape memory polymer
Shape Memory Polymer
Shape-memory polymers are polymeric smart materials that have the ability to return from a deformed state to their original shape induced by an external stimulus , such as temperature change....
s (SMP) and Shape Memory Alloys
Shape memory alloy
A shape-memory alloy is an alloy that "remembers" its original, cold-forged shape: returning the pre-deformed shape by heating. This material is a lightweight, solid-state alternative to conventional actuators such as hydraulic, pneumatic, and motor-based systems...
(SMA). These materials offer significant shape changes at a range of transition temperatures, which are achieved by methods involving infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
, microwave
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...
, supercooling
Supercooling
Supercooling, also known as undercooling, is the process of lowering the temperature of a liquid or a gas below its freezing point without it becoming a solid....
, chemicals and direct heat. The range of "trigger temperatures" for various smart materials means that it is possible to place the products in a heated environment where the outer elements become detached and then move on to a higher temperature zone where internal parts and sub-assemblies are dismantled.
Recently, other materials employed for AD, again by Dr. Joseph Chiodo, have been 'made' smart. For i.e., interstitial layers, sprays, adhesives, engineering polymers, biodegradable components have been specifically engineered to actively disassemble on demand. The repertoire of 'smart materials' and other approaches continues to expand.
Examples of AD fittings
Screws, rivets, ribbons, bars and clips, specially designed to facilitate AD, can be manufactured from smart materialSmart material
Smart materials or designed materials are materials that have one or more properties that can be significantly changed in a controlled fashion by external stimuli, such as stress, temperature, moisture, pH, electric or magnetic fields....
s such as SMA
Shape memory alloy
A shape-memory alloy is an alloy that "remembers" its original, cold-forged shape: returning the pre-deformed shape by heating. This material is a lightweight, solid-state alternative to conventional actuators such as hydraulic, pneumatic, and motor-based systems...
s and SMP
Shape Memory Polymer
Shape-memory polymers are polymeric smart materials that have the ability to return from a deformed state to their original shape induced by an external stimulus , such as temperature change....
s. These will trigger at a pre-determined temperature, depending on the specific application.