1 Introduction

Compared to physical injuries, brain injuries are mostly hidden and invisible. In physical injuries, the extent of injury and healing can be identified while with brain injuries, which might affect the ability of effective thinking, emotion or behavior control or focus depending on the extent of injury, it is often challenging to recognize. Therefore, brain injury is also termed as hidden disability. Even if there is no effect on motor control or daily life activities, the patient might never know if he/she suffers from a brain injury [1]. Such hidden disability is relatively common with over 700,000 Australians suffering from brain injuries which are restricting them in their daily life chores and work. Every 3 out of 4 brain injured individuals are aged 65 or below. Around 2 out of every 3 of these patients are below 25 with 3 quarters being men and requiring lifelong care [2]. Owing to the high ratios of brain injuries in youth, it is estimated that it costs around 8.6 billion dollars per year to treat these individuals [3]. Hence, trying to enable these individuals to enjoy a high quality of life is a priority [3]. We suggest this might be done by embracing a technology solution, e.g., using sensors and actuators to transfer brain signal to affected limb to move [4]. There is already a lot ongoing research happening in usage of wearable technology to track individual’s fitness, health, and medical data acquisition through [5,6,7,8,9,10]. We plan to use a similar technology to record brain signal from a healthy person and replicate this neurological signal to the person suffering from brain injury to activate limb by using an application controlled by either touch/joystick or voice both by user/care giver.

2 Traumatic Brain Injury (TBI)

Traumatic brain injury is a disruption in the normal function of the brain that can be caused by a bump, blow, or jolt to the head or a penetrating head injury [11]. Traumatic Brain Injury (TBI) is caused by an external force, such as a blow to the head, which causes the brain to move inside the skull or damages the skull [11]. This in turn damages the brain. Causes of Traumatic Brain Injury (TBI) include automobile accidents, blows to head, sports/leisure injuries, falls/slips, domestic/physical violence [12,13,14]. Given the limited to no awareness by the general public, the neurological brain damage or brain injury can become a fatal invisible epidemic [15]. The resulting brain damage typically leads to changes in rational thinking, consciousness, abilities of language or emotions [11, 15].

3 Acquired Brain Injury (ABI)

Acquired Brain Injury (ABI) occurs at the cellular level [1]. It is most often associated with pressure on the brain [16]. This could come from a tumor or it could result from neurological illness, as in the case of a stroke. There are different types of Acquired Brain Injury (ABI) [1, 17, 18] but they all result in loss of ability to control limbs.

4 Types of Assistive Technologies for Limb Control

There are several possible technology solutions both for amputees or people suffering from physical disability/brain injury, as briefly described below:

4.1 Semi-automatic Limb or Body Powered Limb

A concept for controlling limbs without employing any sophisticated technology is the usage of a harness control system which was used by amputees to give them a bit of control. Mechanism consist of types of Dacron straps, steel rings, steel wires and springs [19]. As shown in Fig. 1(a), in such systems the amputee uses their body power or exertion to move/control the artificial hand [19]. This kind of harness system can only be used by the person who has some strength and control in their body especially in their shoulders and surrounding areas; if this is not the case then this kind of harness cannot be utilized to make a motion or control the grip of the fingers in hand.

Fig. 1.
figure 1

(a) Trans radial Prosthetic control system used for amputees [19, 24], (b) a paralyzed woman uses robotic arm through thoughts to feed herself a chocolate [21], (c) non-Invasive brain signal transmission to control exoskeleton [25], (d) a real person using technology with wires visible on the arm [26] and (e) MyoPro prosthetic developed by Myomo Inc [27].

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4.2 Fully Automatic - Brain Controlled

These fully automatic limbs can be controlled through will/brain signals of the patient. In one type of control, a small electrode is invasively implanted directly on the brain. In brain implants, the wires are connected directly to the electrode emerging out of the brain/skull [20,21,22,23]. As this electrode is connected to a limited number of neurons in the brains, problems in communication can occur and will require surgery to reconnect the electrode. While in other types of signal communication, the working nerves already present in the limb are connected to the electrode to communicate between brain and limb. Both types of brain connection to electrode require invasive surgery to develop a connection between limb nerves and brain to create a communication channel and get required action or motion.

4.3 Invasive – Brain Implanted Electrode

Another possibility for people suffering from inability to control or move their limbs can be a fully automatic brain-controlled device developed by the researchers at University of Pittsburgh Medical Center Fig. 1(b). This system uses Utah Electrodes (consisting of two beds of needles) implanted in brain through surgery and uses the thoughts of patients to control an artificial limb to do different sets of activities ranging from holding, lifting and stacking varying shapes [21, 22]. Instead of controlling the artificial limb at a distance, if the full arm is covered with similar electronics and mechanisms, it will help in controlling their limbs with their thoughts.

Similar work has been conducted by researchers at Brown University/Blackrock Microsystems [25]. They have used brain signals to control Internet of Things. It is expected that with this technology, paralyzed people can control their TVs, computers, wheel chairs and even autonomous cars with their thoughts [25]. Though this experiment showed remarkable improvement in brain and machine interface this technology is still in its infancy. The problem and risk of getting infection due to the need of cables and connections to the electrode along with gradually loosing reading or accessing the neurons and limiting the control over the limbs still presents a great problem for acceptance by the regulatory authorities and risk of failure of device also makes it less acceptable choice in common.

4.4 Non-invasive – Head Wearable

A joint group of scientists working at Korea University and TU Germany [28] have been successful in using electro echoencephalogram (EEG) signal cap to serve as an interface between exoskeleton and brain through computer. This allows users to control (sit, stand, move forward, turn left and right) the exoskeleton by intentionally looking into a set of LEDs. The setup consists of powered exoskeleton, visual stimulus, wireless EEG transmitter, signal processing unit as shown in Fig. 1(c). Visual stimulus unit consists of 5 LEDs each assigned to different task. The LEDs flicker at different frequency and when user stares at any one of them, the EEG cap reads the EEG and this is used as command to operate the exoskeleton. Using such kind of exoskeleton with electro-mechanical devices, creates a lot of noise which hinders in smooth processing of EEG signals from brain, furthermore, the brain signals generated due to other activities.

4.5 Controlled by Brain Signals in Limb

Invasive-Brain Signal from Implants into Limb:

Researchers from Chalmers University, have developed a technique called Osseointegration [23]. In this technique, the limb is controlled directly by nerves through the titanium implant (OPRA implant systems). As depicted in Fig. 1(d), a real person controlling limb through brain signals. The researchers placed electrodes on amputated limbs and within minutes subjects could control the artificial limbs [23]. Instead of using the implant the similar process could be utilized to send and receive signals for movements and sensation of touch.

Non-Invasive – Fixed to Limb:

For patients suffering from weakness in their muscles or paralysis in their upper limbs (due to a number of reasons including stroke, spinal cord or nerve injury e.g., brachial plexus injury or similar neuro-muscular diseases e.g., amyotrophic later sclerosis (ALS) or multiple sclerosis (MS)), a company named Myomo Inc. has developed a robotic prosthetic called MyoPro [29]. Figure 1(e) shows an example of MyoPro device used by one patient [27, 30]. MyoPro (a myoelectric elbow/wrist/hand orthosis) senses signals from limb through non-invasive method. The robotic prosthetic which senses nerve signals from limb and amplifies that signal to control the motion and action of weakened limb or hand to enable a disabled person perform daily life activities reducing overall cost of care. The MyoPro is customized according to individual patient as a wearable powered brace. It uses nerve signals from the affected limb and powers on to motors to put affected limb into motion/action [30]. This device in fact enables patients to return back to their work and live a normal life, reducing burden on individual, government and overall economy.

5 Proposed Smart Textile Glove

While the preceding has served to highlight the many solutions most of these are not simple and further are often quite expensive, thus, we propose a smart glove which is both a simple collection of sensors and is relatively inexpensive and easy to use as well as highly portable. The proposed smart glove is a combination of textile-based sensors, actuators and integrated circuits. The basic concept is to record the brain signals from a healthy hand for different movements and actions and then conveying these signals to the limbs with healthy muscle cell but suffering from neuron disconnections or damage. As many researchers have utilized same signals to control limbs either through invasive or non-invasive implants directly into brain or in the relevant limb, this appears to be a prudent approach [20, 21, 23, 26, 28, 30]. There is a significant amount of research going on into developing the textile-based limb controllers to sense the movement of the fingers and convert them into electrical signals [31, 32]. Our proposed glove will be working in a reverse manner, communicating electrical signals/nerve signals to the muscles to make motion or control actions. These textile-based limb controllers can help a person affected by brain injury to control their body again using either an app on a mobile/tablet or using voice command through the same app.

Basic elements of smart textile-based limb controller can be divided into four categories including:

  1. 1.

    Textile core (glove, full sleeve glove, socks, full leg stockings)

  2. 2.

    Central processing unit (processing information coming)

  3. 3.

    Input devices (from app through touch, voice or eye ball movement command)

  4. 4.

    Output devices (sensor and actuators, performing movements/actions)

The textile-based limb controller will be custom made according to a person’s physique, needs and choice of material/color. After successful determination of signals and connections between the nerves; the sensors and actuators can be added to textile core. The sensors/actuators in the textile core will be connected to app wirelessly. On input to app either through touch or voice command, central processing unit will match command with relevant nerve signal and convey this nerve message as electrical signal to healthy muscle to perform required activity/action. In this way, non-invasively limb motion will be controlled using an application.

Why textile-based limb controllers?

The textile-based limb controllers can be inexpensively tailor made. There are multiple techniques available to produce them. A wide variety of materials and colors are available. The textile-based limb controller has an aesthetic aspect and can give wearer confidence and bring them out of any feeling disability or depression. The invisibility with choice and variety of color and material can be matched with a person’s fashion appeal and can help them look like a normal person and giving the physically challenged person power to feel integrated into society. This will reduce anxiety and depression leading to suicidal which are very common in persons suffering from brain injury. The textile-based limb controller will be virtually invisible and can give the individual suffering from brain injury a boost in confidence to get back to normal daily life activity ranging from eating, changing clothes, doing house chores, exercising and even getting back to work. In fact, this small change of having textile-based inexpensive limb controller will bring a pleasant surprise in physically challenged person’s life. This will ease burden of care from family members and government. In return it will increase overall productivity of society and bring down cost of care. The comfort of a textile-based limb controller will be far better than any other material (Nylon, wood, metal or composite material). The textile-based limb controller can easily be upgraded with growth of person wearing it; consequently, only sensor and actuators need to be taken out and put into next customized upgraded textile-based limb controller. With textile-based limb controllers, the sensors and actuators can be taken out and replaced where nerve connection is available; making textile-based limb controller customizable anytime.

The physiotherapists can use these textile-based limb controllers to help achieve better results for their patients. The textile-based limb controller can also record the movement and exact path of movement, enabling physiotherapists to understand quality of exercise and improvement in results. It can also help physiotherapist to monitor patients’ exercise pattern and improvement in their limb control. As movements and exercise patterns are recorded by textile-based limb controller, a single physiotherapist may attend increased number of patients and can offer services on even more competitive rates. In a similar way, a textile-based limb controller can be utilized by patients at home or in community care settings away from physiotherapist place. This has the added advantage of reducing the need for extra resources for commuting and waiting to get treatment done at an appointment.

6 Conclusion

The number of accidents and incidents are increasing with high speed motor and longer healthy life styles, which in turn leads to higher brain injuries and increasing overall cost of care and higher level of depression and anxieties in patients suffering from such problems. These incidents quite often result in disability of single or multiple limbs. Different techniques as presented have been employed to help such patients, such as brain implantations either into brain or relevant limb to control it. But these techniques are extremely expensive and not available for all patients. Our proposed smart textile garment (glove) will use integrated sensors and actuators to control limb for rehabilitation and daily life activities. The signals from a healthy human being can be recorded and stored into computer system. These signals then can be utilized through information technology to develop an app which can be installed into smart phone/tablet to be used by patient or care giver using voice command or touching the screen. The same commands can be conveyed through joystick controls to make it another easy option, similar to the joystick controls on a wheel chair. Patients can control their own organs as they control their wheel chair. Such systems will not only bring brain injury patients out of depression but also make them a part of main stream society as these smart textile-based limb controllers will give patients a look of a normal person with no visible wires or other prosthetics. This will lead patients to live a more independent, high-quality life where they can work, socialize and inspire others to live a better life even with a brain injury.