CC BY
35
UDC 621.865.8
VARIETIES OF EXOSKELETONS
Oleg Vladimirovich MALYUGA
OnyxCom LLC Krasnogorsk, Russia oleg@onyxrobot.com
Abstract
Exoskeletons are created to increase the muscular strength of a person and are intended mainly for two categories of users: for those who need rehabilitation for diseases of the musculoskeletal system, as well as for workers of physical labor. In this case, the exoskeleton can not cover the whole body, but only a certain part of it. For example, the hand, as in the case with the mechanism of x-Ar from Equipois company.
In the process of human life and its environment form a continuously functioning system of "man-habitat". Acting in the system of "man-habitat", a person continuously solves two main tasks: to ensure their needs for food, water, air and the creation and use of a system of protection against negative impacts from both the environment and from their own kind. The process of life is safe and comfortable human interaction with their environment, which may be industrial, urban, domestic or natural environment. Specialists in biomedical engineering can participate in the creation of devices and equipment, in the development of new procedures based on interdisciplinary knowledge, in research aimed at obtaining new information to solve new problems.
Keywords: exoskeleton, innovative devices, development, knowledge.
Introduction. Intelligent technical devices with qualitatively new properties-robots-become a tool that contributes to the greatest functional consistency and mutual integration of all elements of the system under consideration. Such innovative devices, developed on modern mechatronic principles, not only increase the functionality of a person, but also give it completely new properties, allowing, in some cases, especially when performing routine, harmful and dangerous types of work, to completely abandon the direct participation of a person [Androwis, 2018, 9]. The creation and use of such devices is the key to ensuring the safety and high efficiency of a number of tasks aimed at improving the human environment:
1. improving the quality of life of each individual, through the integration of robotic systems in his way of life and improve the overall environment;
2. creation of robotic devices that allow people with physical disabilities to lead an independent lifestyle (creating an accessible, barrier-free environment);
3. improving the safety of life of employees of enterprises, which are the most important value not only for the state, but also for each individual enterprise, the success of which is primarily determined by the team;
4. creation of robotic devices that improve the economic efficiency of production and performance of work in conditions of limited resources;
5. reducing the influence of the human factor-reducing the probability of making wrong decisions [Baunsgaard, 2018, 810].
In recent years, a new branch of science and technology - bioengineering-has emerged and is rapidly developing all over the world. Modern bioengineering is based on knowledge in the field of medicine, biology, mechanics, electronics, modern methods of computer control and information processing. This engineering discipline aims to use knowledge and experience to find and solve biology and medicine problems. Bioengineers work for the benefit of humanity, deal with living systems and apply advanced technologies to solve medical problems. Among the important achievements of bioengineering are the development of artificial joints, magnetic resonance imaging, pacemakers, arthroscopy, angioplasty, bioengineered skin prostheses, renal dialysis, heart-lung machines [Carosio, 2018, 480].
Bioengineering makes a significant contribution to the development of scientific and technological progress. Many things that previously met only in fiction novels writers, today same have become, if not
mundane, then well real. For example, costumes, which are used by the heroes of science fiction films and computer games, already exist in reality and allow a person to become stronger and faster.
In Russia, biotechnology and bioengineering are included in the list of nine top priority research areas. Unfortunately, the scale of bioengineering research in Russia is very different from that in the West: the state budget allocates a thousand times less money than in the US [Deng, 2018].
Practical application of achievements in bioengineering technology is significant and socially significant. Among the most important social the rehabilitation and social protection of persons with disabilities, which would enable them to become full members of society equally with healthy people, to take an active part in all aspects of public life, is one of the main problems currently facing. It is the achievements of bioengineering that can significantly improve the quality of life of people with disabilities and patients with disorders of the musculoskeletal system and undergoing rehabilitation [Exoskeleton, 2005].
Exoskeletons - one of the innovative bioengineering technologies, which is to develop special mechatronic devices in the form of an external human frame, which increases its muscular strength. This technology allows you to combine human intelligence and the power of the machine, as the operator becomes part of the machine. The exoskeleton is a device that is "put on" over the clothes on the human body.
Motorized legs, which are fixed with special brackets and belts, are powered by a battery located in the shoulder backpack. The device uses special sensors to detect the movements of the owner and" translate "them into movements of motorized"joints". This frame can be built into a special suit, and is able to repeat the biomechanics of man, greatly increasing his physical strength. The principle of operation of the device is the same as that of mechatronic devices: sensors give signals to engines, the action of which muscles need to be simulated [Guanziroli, 2018].
The main objective of the project is to create a scientific basis and tools for the design of bioengineering robotic devices to improve the quality of human life - an exoskeleton that extends its (human) functionality through the use of mechatronic principles of motion control actuators - with feedback and intelligent electronic system of recognition of control signals. The use of such solutions in the creation of an exoskeleton will provide a significant advantage over analogues, with special attention to adaptive control systems, sensors, navigation, rational use and energy recovery [Heinemann, 2018, 260].
The social and social significance of the project is to provide training and retraining for the national economy in these sectors in close cooperation with enterprises of all forms of ownership working in the real sector of the economy.
Materials and methods. Hand-exoskeleton Equipois x-Ar is designed for workers who are on duty constantly dealing with heavy objects. The mechanism is worn on the arm and has a supporting structure that runs along the entire back. Thus, the movement of each heavy part takes on the exoskeleton, and its weight is transferred directly to the floor. As a result, the productivity of the worker increases. Finally, this development has a significant advantage over other commercial exoskeletons-the price. It is from two to three thousand dollars, and the car will go on sale approximately in April [Leclair, 2018, 9].
Fig. 1. Robotic arm Equipois x-Ar
The development of Argo Medical Technologies is designed to help paralytics walk, and people who have experienced various injuries can use ReWalk as a tool for gradual rehabilitation. After clinical trials in the US and Israel, the device is finally ready for mass production-in January, the exoskeleton will be sold in rehabilitation centers around the world.
ReWalk weighs only 3.1 kg - in such a light weight, the developers managed to accommodate two motorized "legs" with motion sensors, all the necessary elements for attachment to the body, a backpack with a control computer and a battery. The latter is capable of providing three and a half hours of continuous operation, but the creators do not report the recharge time [Lerner, 2018].
In 2008, ReWalk was estimated by the creators at $20 thousand, but in reality the exoskeleton will be sold for $100 thousand. Maybe, for the Western health care and insurance system, this amount is not significant, but in our reality only the wealthiest people will be able to afford ReWalk [Li, 2018].
Fig. 2. ReWalk
Results and discussions. Currently, the development of new technologies allows to create electronic and mechanical devices that can significantly enhance the natural capabilities of man-exoskeletons. First and foremost, these devices are interested in the military and for military purposes is conducted most of the research on the topic of exoskeletons. By order of the us Agency for advanced research (DARPA), several prototypes of existing exoskeletons have already been created and work is underway to finalize and implement them. Successful preliminary tests of these prototypes prompted the us military to create also their underwater analogues, allowing in the future to increase the speed of movement of combat swimmers under water [Molteni, 2018].
By order of DARPA engineers from the Institute for human and Machine cognition (Institute for Human and Machine Cognition) began work on a project called PISCES - Auxiliary Autonomous exoskeleton for swimming (Performance Improving Self Contained Exoskeleton for Swimming). Developments on the theme of PISCES were based on the success of previously created by DARPA device called PowerSwim.
Essentially powerswim up is a system consisting of two fins and a corrective mechanism. The corrective mechanism is designed so that when the swimmer moves under water, he makes these fins move in the same way as the fins of fish or Dolphin tail work. As a result, a person spends much less effort to move
underwater and can swim 150% faster. Fin powerswim up allows combat swimmers to get to the destination faster, thus saving oxygen and power [Nasiri, 2018].
Fig. 3. Powerswim up
Unlike PowerSwim, the PISCES system is a full-fledged exoskeleton and not just transmits the energy of human movements to the fins, but also takes over part of this work. At the moment, two concepts of the PISCES system have been developed: the first is aimed at strengthening the movements of the swimmer in the lower part of the body, and the second goes a little further, trying to simulate the same movements that penguins and dolphins use for swimming. The most promising is the second concept, as it involves not only the lower but also the upper part of the swimmer's body.
Military of DARPA expect that this approach to underwater movement will allow combat swimmers quickly, silently and with minimal loss of oxygen and forces to get to important enemy targets. Unfortunately, nothing is known about the technical characteristics of this interesting and promising system.
The Japanese company Cyberdyne suggested using the exoskeleton HAL (Fig. 2.8.) for work at nuclear power plants, and also for analysis of blockages on "Fukushima-1". Motorized limbs will allow workers to lift heavy objects, and a sealed suit provides protection against radiation. Now for these purposes it is necessary to use more complex and bulky structures [Rahmani, 2018].
Fig. 4. Hal exoskeleton
Representatives of Cyberdyne noted that the new type of exoskeleton HAL allows the worker at the scene of the accident to keep the weight of the tungsten protective suit without feeling its severity. Light protective suits are able to stop only weak forms of radiation-they are worn not to create a common barrier to radiation, and to suspended in the air isotopes do not fall on the body of the worker.
Full protection that can stop radiation is too heavy for a person, so when eliminating the consequences of accidents, lightweight versions of such suits are worn, and work for each person continues for a very short time, so that the dose of radiation is small. However, with the Hal exoskeleton, workers will be able to put on
protection from heavy tungsten plates, which stop even high-level radiation and allow to increase the duration of tasks. Today it is the most favorable option for the designed product.
Technical parameters:
The load capacity of the exoskeleton is 80 kg;
Working time-6 hours;
Number of hinges-16;
Consumes energy-50 am\h;
Weight-30 kg;
You can adjust the dimension;
Waterproof;
Results and discussions. In the developed project, the batteries of the OPzS brand are considered. To date, the classic lead-acid batteries OPzS in Russia and foreign countries are manufactured in several types: monoblocks or individual elements. OPzS batteries are standard low-maintenance (require a minimum of time and maintenance costs) acid-lead batteries with liquid electrolyte.
OPzS batteries are shell batteries that have positive plates that meet the standards DIN 40736.1, GOST R IEC 896-1-95 (IEC 60896.1). This type of accumulators is intended for systems of reserve power supply in the industrial equipment, telecommunication systems, industrial installations, nuclear, hydro - and heat power stations to standard uninterruptible power supplies. According to VDE 0107 and VDE 0108, OPzS batteries are sources of electrical current in security systems.
The average battery life of OPzS from the company "NPO SSK (SSK group)" is from fifteen to twenty years. This period is an undoubted competitive advantage of batteries from SSC. Also, the frequency of adding water to the battery - once every 2-3 years, which allows to minimize the cost of maintenance of OPzS batteries. A fully charged element of such a battery can be stored for at least six months before the next charge [Verrusio, 2018, 935].
In some situations, OpzS batteries can provide a DC load of 100%. In this case, the elements of such batteries operate in parallel(standby). If necessary, lead-acid batteries can operate in a cyclic mode in certain configurations.
OPzS batteries from the company SSK attract customers with high reliability and efficiency, as well as a competitive price. For the installation of these batteries do not require additional time and technical means. The main body of the lead-acid battery types OpzS is made of SAN plastic, which thanks to its transparent base allows you to control the electrolyte level(full charge, the need to recharge the battery). Electrolyte, which is the basis of OPzS batteries is an aqueous solution of sulfuric acid.
Field of application of accumulators: telecommunications; telephone and Telegraph stations; systems of mobile and paging communication; systems of space communication; radio relay stations; uninterrupted power supply of UPS; languid, heat and hydroelectric power stations; transformer substations of electric networks; reserve systems of solar power; systems of the organization and management of air traffic; systems of safety and defense industry; oil and gas and mining industry; Railways. General specifications batteries: low maintenance lead acid battery series, OPzS company SSK Group with positive plates in armoured version designed for backup power supply of the object. Batteries have a long service life, over 20 years, and can be used in cyclic and buffer mode.
Features: classic battery with liquid electrolyte; high reliability and efficiency; low maintenance; storage time of a fully charged element to recharge is 6 months; frequency of water refilling 1 time in 2-3 months.
Tubular positive plate, made of lead-antimony alloy with low antimony content (not more than 1.7%) according to the shell technology. The body is made of transparent SAN plastic, which makes it easy to control the electrolyte level. Electrolyte is an aqueous solution of sulfuric acid with a density of 1.23 g / cm?. The plugs are made of explosion-proof. The borns are made of lead with brass inserts to improve conductivity. The separator between positive and negative plates is made of microporous, corrugated material. The inter-bridge made of copper. Fastening of the jumper to the born is made by means of a bolted connection.
For carrying out concretization of the tasks necessary to identify its boundaries. To begin with, we list the main factors: the human factor, the capabilities of modern technology, the requirements emanating from the situation.
Human capabilities, time fruitful, active work in extreme conditions is not more than 5 hours. From that time, subtract approximately 2 hours by road to the accident site from HQ and back. Remains 3 hours to complete the mission. Even with the most exaggerated calculation is obtained 1 hour continuous work welding equipment. From this figure, you can get the battery criteria equal to 300 amps per hour. Batteries are different and in this case it is necessary to pay attention to the mass.
With regards to the technical part, it should be noted that throughout the task will be pursued the goal, to reduce the size and weight of the equipment to the maximum. Starting from the prototype, the maximum load capacity is 80 kg.
The lightest battery that meets these criteria weighs about 30 kg, an example is the model of the acid battery of the OPzS series, which will be discussed in more detail below. Thus, the minimum mass of the battery is 30 kg.
Next, we will discuss the inverter. The transformer is not considered, since any model of transformer has a much larger weight and dimensions than the inverter with the same technical characteristics. Since in this project situation it is desirable to pursue a smaller size and dimensions - well suited model of single-phase welding machine VME 160 (VM 50.00.000). This is currently the most popular model of the VME series inverters. This welding machine combines the necessary qualities of a high-class inverter, such as: a high percentage of the duration of the inclusion at the maximum current (PV 70% at 160A), minimum dimensions, weight and many others. The inverter gives a softer and more elastic arc, and its amazing performance, size, weight — are a great advantage when working in critical areas.
Weight: 2.5 kg.
Overall dimensions: 190 X 240 X 70 mm.
The breathing apparatus is one of the key parts of the system. Respiratory apparat more overall and has a relatively large weight, it the layout in the suit reboot more attention [Wei, 2018].
The control system also attracts innovation to simplify and speed up the process of the operator. A small monitor and wireless connection are used to receive information. Joysticks are used for control. The developed product becomes a complex of the equipment which is closely connected on functionality.
Fig. 5. Scheme of complex systems of the developed product
Conclusion. To solve this problem, the material on new technological capabilities was collected. The collected information was actively used in the development of the designed product. Also, the collection of information allowed to create a vision of the prospects for the development of this field of human activity.
An additional task can be considered an attempt to revive the cultural origins of Russia. Searches were conducted in this direction. The result of this work can be considered quite clearly accentuated design concept in the old Russian culture.
It can also be noted that the task of the project is currently quite relevant in the world. Developments in many countries of the world, in different directions of human culture are actively conducted. If we look at the development trends in this area, we can say with sufficient confidence that the exoskeleton in a relatively short period of time can repeat the scenario of technical and aesthetic evolution, as it once did the car, in the objective world of man.
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