Authors: Hakancan Öztürk, Arda Bulut and Mete Uz.
We have more seen wearable devices in nowadays, and in the near future we will see much more applications. In this blog, we are going to focus on two major application fields of wearable devices, which are military and health technologies, then disscuss the importancesy of privacy of the health data that collects from this wearable devices.
War never changes, but technology does. With the improvements and new inventions in technology, war culture is also advancing rapidly. And the technologies in any industry are being implemented to the military culture, one of the crucial being the wearable technologies. The decrease in the size of ordnance let armies equip their soldiers with high-tech wearable systems such as smart combat glasses, exoskeletons, and biosensors.
Smart Combat Helmets
Smart glasses are getting more conventional every year and their applications are getting more widespread. However, the focus will be on the military use of smart glasses. There have been tons of advancements in aerospace engineering and fighter jets nowadays are capable of reaching unbelievable speeds and carrying dozens of tons of explosives and ammunition. However, the operators of those killing machines, are still mostly humans instead of machines so they have limited views. When the operation weather is foggy or it’s night time the jets are basically useless without smart glasses. All of the modern fighter pilots have modern combat helmets with integrated smart glasses on them. “The helmet is much more than a helmet, the helmet is a workspace,” said the Air Force Chief of Staff General Mark A. Welsh III at a 2015 briefing on the new Lockheed Martin F-35 Lightning II fighter jets’ pilot helmet. The new headgear feeds real-time data such as airspeed, altitude, direction, and classifies other aircraft as enemy or friend. This super helmet also lets the pilot change the real-time video feed with thermal imagery or night vision. The downsides of these helmets are being heavy. Since there are many sensors and integrated circuits, the helmets can go up to 6 kgs , and they weigh approximately 9 times as much under high-g accelerations. This technology is advancing at a high pace, and experts believe that the future jets will be remotely controlled by a pilot with a helmet while he is pressing some buttons in the military post.
Exoskeletons are the gadgets that the operator wears like an item of clothing for additional power, agility, and endurance. The most famous exoskeleton is the Iron Man’s suit which is the perfect way to turn a normal human being into a killing machine. There are several exoskeleton prototypes for military use that are still developing. According to the article  on the world’s biggest aerospace, defense, and arms company Lockheed Martin’s website, the key features of their exoskeleton ONYX are listed as such: “enhances strength and endurance to carry taxing loads over distance, enables better handling and support for heavy weapons, reduces metabolic cost of transport to improve endurance and reduce fatigue, increases the ability to traverse stairs, inclines, and rough terrain, especially with load, and reduces stress on leg muscles”. That list goes on, however, there also are strong oppositions to the military exoskeletons. In the “Why Military Exoskeletons Will Remain Science Fiction” article  aerospace and defense engineer Vikram Mittal argues that the military exoskeletons are far from being efficient and useful. He lists the technical obstacles before having a well-functioning exoskeleton as such. The first of them is that the machine itself is not smart enough to predict the motion of the operator and the embedded sensors will be delayed so the parts will be laggy resulting in soldiers “feeling like they are moving through a pool of Jell-O,”.  Another challenge is that the exoskeleton attachments limiting the full range of motion of the joints. Mittal criticizes the current prototypes which aim to support all body as “Although actuating a knee is straightforward, more complex joints, such as hips and ankles, require very advanced, multi-dimensional actuators,”. He finalizes his article by saying the exoskeleton technology is more likely to stay as fiction. 
All these technologies come with a cost which restricts the soldiers on the field: energy. The energy requirement is the sturdiest barrier against wearable technologies, however, there are many companies coming up with products addressing this problem. Since it’s impossible to charge infantry units like a smartphone, their energy storage must also be mobile. A Canadian Military Exo Development company named BionicPower aims to solve this issue by using the soldiers’ mechanical energy. They define their product’s mission on their website as such: “Today, we are focused on developing our PowerWalk® Kinetic Energy Harvester for military use and began multi-unit field trials with the U.S. Army, U.S. Marine Corps, and Canadian Forces this year“.  They state that a soldier carries around 8–9 kg in batteries on a three-day mission. And using PowerWalk a soldier would be able to generate around 12 watts walking and up to 30 watts jogging of power by optimizing the power output using the built-in microprocessors. For comparison, 12 watts is equivalent to generating enough energy to charge 4 mobile phone batteries with an hour-long paced walking. This would drastically decrease the soldiers’ loads and the unit’s reliance on resupply while increasing the effective duration of operations.
How it Works
Biosensors are devices that measure concentration of a substance of interest in chemical reactions that happen inside the body of an organism or the environment.  A biosensor is made out of a transducer which converts the biological feedback to an electrical signal and a specific biological component which does the sensing part. The bioelement can range from macromolecules such as proteins or nucleic acids to more complex biological structures such as microorganisms, organelles or pieces of tissues. The signal generated when the biomaterial interacts with its environment is converted into an electric signal via the transducer which then can be analyzed into meaningful data. 
A Brief History
The first biosensor was developed in 1962 by Leland Clark Jr. He wanted to measure the oxygen concentration in blood using an electrode. He covered the electrode with a cellophane wrap, a semipermeable polymer which only allows low weight molecules such as oxygen to pass through , to achieve this. He further developed his invention by trapping high concentration glucose oxidase enzyme within another membrane, which converts glucose to D-glucono-δ-lactone and hydrogen peroxide when oxygen is present, it is also considered the ideal biomaterial for biosensors , thus the first biosensor was created.  Biosensors used in the food industry still use this principle to measure the glucose content in products.  Thanks to the advances in nanotechnology and synthetic biology, modern biosensors can be implanted to an organism and the biomaterial can be very specific such as a synthetic protein or a genetically engineered microorganism that is programmed to generate very specific outputs with specific selectivity to the desired analyte. 
Biosensors are used in the food industry and environmental control to measure concentrations of specific compounds. This includes food products and soil composition used in agriculture.  In health care biosensors are used for in vivo detection of certain compounds in the human body, for example the glucose concentration of blood. This eliminates the need for laboratory analysis of blood. This technology can also identify risk of disease, for instance cholesterol biosensors can determine if a patient has a risk for cardiovascular disease.  A special type of biosensor called immunosensors can detect the formation of antigen-antibody complexes to detect certain diseases or quantify the response of the body to a drug which then can be used for drug design.  Nucleic acid based biosensors can detect cancerous cells or certain genetic diseases via hybridization of cfDNA and ctDNA fragments in the blood stream that is the byproduct of necrosis or apoptosis of cells  with synthetic oligodeoxynucleotide probes that are integrated to the biosensor.  Whole-cell biosensors use genetically altered cells, prokaryotic or eukaryotic, as their biomaterial to measure certain metabolic processes.  Fluorescent biosensors which use a fluorescent protein as the biomaterial are used in imaging of cells and quantifying genetic expression and molecular activity. 
The Future of Biosensors
Research into biosensors are towards increasing their reliability, sensitivity and selectivity.  In the future we can wearable biosensors can assist people by giving them access access to a mobile dashboard which tells them if they are at risk of disease and can help them make healthy decisions in their daily lives. We can also see usage of biosensors in environmental control, for example a biosensor can alert the owner if their pool is contaminated or their air-conditioning unit has the presence of pathogens. Biosensors are also used in cancer research and in development of effective drugs. 
Brain computer interfaces (BCI) are a developing technology that aims to translate brain signals into commands that a computer can interpret and execute.  The potential uses for this technology go beyond communicating with a computer. It has been shown that BCI’s can help people deal with neurological diseases such as Alzheimer’s.  In this section we will talk about how this technology works, its potential uses and the most popular application Neuralink.
Electroencephalography (EEG) is a technique that has been developed in the early 20th century that can record brain signals via electrical activity in the brain.  Throughout years such signals have been analyzed to make sense of it as interpretable data.  EEG devices could also only be used in laboratories as they were too big to reallocate. Near the end of the 20th century such devices became portable and thanks to developments in nanotechnology EEGs can be placed in subcranial regions.  These breakthroughs allowed BCI technology to read brain signals and convert it to commands in real-time today.
Most basic use of a BCI is communication with a computer. This may include something as simple as moving the cursor on the computer screen. From this concept a myriad of potential uses can be derived. The commercial uses of this technology include environmental control. Recent developments in IOT allow us to connect all our devices into a network. With the help of a BCI a person can connect to that network and can access those smart devices by just thinking about it.  Medical uses of this technology provide a solution for disabled people. Prosthetic limbs can be controlled via a BCI, locked-in individuals can communicate with the outside word. BCIs can also assist in relearning physiological functions that have been impaired because of neurological or psychological diseases.
Neuralink is the latest development in BCI technology and is the most well known. Its improvement over existing systems is that it is much smaller and efficient. It works via threads of flexible microelectrodes that are biocompatible. These threads are sewn into the relevant regions of the brain with micron precision by a neurosurgical robot that recognizes regions of the brain and has depth tracking, therefore it does not damage any essential part of the brain. Those threads are then connected to a computer that can analyze brain signals and stream neural data. The aim of Neuralink is not only to give commands but it can also stimulate parts of the brain via precise electric signals.  It can help people with disabilities as well as become a great platform for neurological research. It can, for example, restore hearing to a deaf person by electrically stimulating the brain to produce the same effect as a neural signal from the ears normally would.  In an interview, Neuralink was also said to be capable of recording and transplantation of memories.
Privacy of Health Data
Although wearable technologies (WT) have brought many advantages differing in various areas, security vulnerabilities are still one of the major concerns. Debates are not for nothing because it has been shown in an HP research that the most preferred 10 smartwatches have some significant security vulnerabilities, including poor authentication, lack of encryption and privacy issues.. The most noticeable concerns about the security of WT are insufficient authentications and danger of the information that will be seized.
Firstly, it is controversial whether WT are embedded with highly protective precautions or not. Most WT transmit their data which have been collected by sensors of the device, via Bluetooth or Wi-Fi. Due to threats of attacks, the data should be protected by encryptions based on a process that encodes a message or file to make it reachable or seen able for certain people or devices. If the data is not under protection, an attacker can simply make use of sniffers to steal unauthorized data by detecting the broadcast signals while a wearable device is communicated over Bluetooth.  Moreover, worse circumstances might occur owing to lack of authentication. Since Cloud accounts offer accessibility to files at any time or place, WT is mostly used with a Cloud account in which personal data is stored. The one advantage of Cloud is they can work synchronized by smartphones. This feature becomes a threat for the WT not including strong authentication because hackers who are able to reach signals transmitting from devices to the cloud, might reach one’s smartphone as well.
Other significant vulnerability about WT is hijacking personal data by the third people. Some WT such as Fitbit or Apple Watch, collect health related data, including heart rate and body temperature. This information can be used for self-interests of some third-party companies. Insurance companies may also take this advantage to create a “gray market” for getting users’ health information data.  For instance, medicine companies could alter the data and despite not having any disease, one might consider himself/ herself as ill by referencing detorted data.. This also causes doctors to be misled and maybe prescribe some medication produced by the company which changed the data. Furthermore, it is also possible for cyber attackers to reach your phones through the wearable devices. This brings about a change for hackers to have your critical information stored at your phone, including addresses, credit card numbers, passwords etc.
In conclusion, wearable devices might be challenged with some security vulnerabilities such as lack of authentications and risk of hijacking data. Since it is an ever-developing area, these concerns are thought to have been solved in near future. Especially, with help of some platforms such as SecuWear which aims to tackle issues holistically and providing an appropriate environment for producers in order to conceptualize problem, and usage of biometric systems, including fingerprints or retina scanning, vulnerabilities could be solve readily.
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