As technological innovation is fused into the rehabilitation process, it gives conventional therapy a new direction with the products of interactive nature and easy to measure techniques. In the recent years, virtual reality based game therapy has turned out to be a promising option for post-stroke patients since it engages patients with fun based exercises during rehabilitation process. It also triggers their neuro-motor functions and accelerates the recovery process. Nevertheless it is necessary to extract some valuable information from the joint movements to measure the recovery condition of patients. Most of the designed games have introduced features to make them interesting as well as challenging for patients, however, only a few measure the joint parameters. We have designed a Kinect based game in Unity3D platform where patients can play game by moving their joints which results in different orthopaedic lessons required for rehabilitation therapy. In contrast to many Kinect based games where only joint movements are considered for playing the game, we have also introduced voice control through speech recognition and feedback provided in terms of audio-visual command to enhance patient’s engagement. Different joint parameters such as trajectory, range of motion, joint velocity, acceleration, reaching time and joint torque are also measured to help quantify the heath condition.

Fine and gross motor skills of the hand are essential to complete the work of surgery. During examinations and surgery, the hand becomes a surgeon and a medical professional’s first point of contact with a patient, as they use their hands to perform tasks with various tools while wearing gloves. The anthropometry of hands and the interaction of the tool can affect the probability of developing a musculoskeletal injury [3]. Tools for healthcare professionals are typically designed using male anthropometric data taken from only one position using tape measures and calipers. The problem with this approach is that humans are rarely in these positions when carrying out everyday tasks and hand measurements and form change with movement. This paper discusses a new method of capturing dynamic hand anthropometry through the use of 3D scanners, to address traditional anthropometric hand data’s limitation. Based on an initial assessment of surgical instruments, six functional hand grasps were selected and compared to traditional hand anthropometric poses. Using these poses, a pilot study with one male was conducted. In total 65 measurements were gathered through 8 poses. The positions with the largest range of measurement change were: Total Hand Length-Palmar with 48 mm, Total Hand Length-Dorsal with 39 mm, and the tip of the first digit through webspace to the tip of digit 2 (Web) with 26 mm. Understanding dimensional change in select areas of the hand is essential to developing more ergonomic, better fitting products for surgeons and medical professionals. A 26–48 mm dimensional change can have a significant impact on the positioning of surgical tool properties, as well as the functionality of the tool and precision of work for surgeons and medical professionals with different hand sizes. This pilot study demonstrated the feasibility of using functional hand grasps as a basis for collecting hand anthropometric data using a 3D scanner.

According to statistical data, approximately 800,000 individuals across the United States have strokes each year [2]. A stroke event causes neurological and orthopedic deficits, such as weak muscles, decreased proprioception, and spasticity [6]. To regain function, increase motor skills, and retrain muscles, many stoke survivors utilize aquatic therapy as a form of rehabilitation [14]. Typically inside water, the lower body part of a person has to carry 75% less weight, This decreases the effect of gravity allowing increased joint range of motion [6], [13]. This also helps increase muscle strength as water offers about 600 more resistance than air [13]. The water temperature also helps decrease pain, spasticity, and rigidity [13]. The uniform pressure along with buoyancy contributes to an improved balance of the body [13].

The human hand has extraordinary dexterity with more than 20 degrees of freedom (DOF) actuated by lightweight and efficient biological actuators (i.e., muscles). The average weight of human hand is only 400g [1]. Over the last few decades, research and commercialization effort has been dedicated to the development of novel robotic hands for humanoid or prosthetic application towards dexterous and biomimetic design [2]. However, due to the limitations of existing electric motors in terms of torque density and energy efficiency, the design of humanoid hands has to compromise between dexterity and weight. For example, commercial prosthetic terminal devices i-Limb [3] and Bebionic [4] prioritize the lightweight need (450g) and use 5-DOF motors to under-actuated 11 joints, which is only able to realize a few basic grasp postures. On the other hand, some humanoid robot hand devices like DLR-HIT I & II hands [5] prioritize the dexterity need (15 DOF), but weigh more than four times than their biological counterpart (2200g and 1500g, respectively).

Nearly half of individuals with stroke experience some form of long-term disability and stroke is one of the main causes of wheelchair use in the United States [1]. Early rehabilitation in the acute phase of stroke has been shown critical to promoting motor plasticity and patient outcomes. However, research shows that only 32% of the time during inpatient rehabilitation is spent in active therapy, while the rest of the time is spent on other activities around the ward [2]. For walking impairment, it is especially important for patients to experience similar force loading and practice the patterning of gait in order to recover [3]. However, in a typical therapy session focused on gait rehabilitation patients only will take about 300 steps on average. This is far below what has been thought needed for humans to learn how to walk [4].

Magnetic resonance (MR) imaging (MRI) has become the preferred method for medical diagnosis due to high resolution images and lack of ionizing radiation. Recently, the potential for using MRI to obtain real-time image feedback for targeted therapeutic procedures such as targeted biopsies and injections has been explored [1]. Some devices designed for intra-MRI use exist and more such devices are currently being developed and researched. Procedures often require precise positional targeting, such as injections and biopsies, and an MRI safe controlled-motion stepper motor is an ideal choice for actuating these mechanical devices. Some such drivers have been developed, but for various reasons, none are considered to be the standard for MRI use at this time. Therefore, a new design combining certain aspects of previous motors has been developed, making use of newer three-dimensional (3D) printers with extreme accuracy. Presented is a small, low-cost plastic four-cylinder piston stepper motor which is actuated by pressurized air. Connected to a plastic gearbox, this motor is capable of driving a rotational shaft at torques of up to 20 N·mm by increments of 3.6 degrees.

Advances in ankle-foot orthosis (AFO) technology have been trending toward more powerful and lightweight devices. A hydraulic series elastic actuator (HSEA) was explored to design a lightweight powered AFO that meets the high peak power demand of ankle gait. With its excellent power density and its ability to separate the power supply from the actuator using a hose, hydraulic power was used, combined with an SEA that takes advantage of the high-peak and low-average power profile of ankle gait to store energy and release it during the push-off stage of gait. The parameters required for the SEA were determined and validated using simulation. A gait pattern that would require 235W of motor power was able to be tracked using a motor rated at 95W. The actuator weight of the hydraulic ankle-foot orthosis (HAFO) at the ankle was 0.35, which is 43% of an equivalent electromechanical system. A novel design of an HSEA with a clutch capability is proposed for future HAFO applications.

Parkinson’s disease is a neurodegenerative brain disorder that occurs when a patient’s body stops producing dopamine. This chemical is essential in transferring motor commands between the substantia nigra and the corpus striatum which enables smooth, intentional movement in the body. Because this transmission line is degrading, about 68% of the Parkinson’s population reports falling [1].

Spondylitis is a very common back and neck ailment that is reported to account for one-third of social problems causing difficulty at work. It is caused due to the inflammation in vertebral joints. Its condition goes undetected until the symptoms, such as that of severe pain, develops. It causes stinging pain which is focused around cervical region of vertebra, the shoulders and the lumbar region of the spine. Accordingly, it is classified into three types: cervical, thoracic and lumbosacral spondylosis. This is different from spondylitis which causes pain due to inflammation. Many existing devices use electric current to bring relief from pain. Transcutaneous electrical nerve stimulation (TENS) is one of the most commonly used devices in this aspect. However, though this has been able to bring effective results to its patients, there is a whole lot of controversy in conditions it should be used to treat. Studies have shown these devices to bring relief by suppressing the signals from the brain. They are not advised for patients with pacemakers or any kind of electronically powered implantable devices. They are less effective where the skin is numb or in places where there is decreased sensation. It depends entirely on the working of the nerve beneath the surface and may cause irritation on the skin if the current is too high. Moreover, these devices need to be avoided in area where infection is present. High precaution needs to be taken when working with epilepsy patients and pregnant women; the electrical stimulation can interfere with the fetus development. With such a wide range of drawbacks, there is a need for a mechanical solution which can redress these problems and provide an effective and ergonomic solution. Along with overcoming the present barriers, research has been done to demonstrate the positive effects of vibration in increase of bone density, increase of muscle mass, increase of blood circulation, reduced back pain, reduced joint pain and boost in metabolism. The given paper discusses a device wherein vibrational motors have been incorporated, under the control of a microcontroller, to generate the requisite g-force needed for the purpose of pain alleviation and increase of bone density.

Parkinson’s disease (PD) is a degenerative disease with diverse clinical features. At present, there is no definitive test for the diagnosis of PD [1]. Instead, PD is diagnosed using clinical criteria which are based on the presence and presentation of signs such as rest tremor, bradykinesia, rigidity, loss of postural reflexes, shuffling gait and freezing, as well as non-motor symptoms. Various treatments, ranging from physical therapy and medications to invasive treatments, can help relieve some PD symptoms. These treatments need quantitative monitoring and efficacy evaluation methods in order to provide higher quality, patient-centered care. A quantitative assessment of the patients’ clinical symptoms can also provide a timely alert to adverse events [2]. A variety of devices employing sensors with the purpose of monitoring PD patients’ symptoms were developed [3, 4]. Most of these devices are costly and / or complex in operation and maintenance, which limits their practicality in busy hospital / clinic environments and for home use. Moreover, they do not provide appropriate solutions for monitoring more severe cases of PD, where the patient requires a walking aid such as a cane or walker.

Parkinson’s disease (PD) is a neurodegenerative disorder known to affect movement. Approximately seven million people around the world suffer from PD [1]. Tremor in one hand characterizes the onset of PD. Population suffering with PD shows symptoms of slowed movement. Consequently, PD patients struggle to complete a simple task like picking up a book. This slowness of movement is called bradykinesia. Bradykinesia measurement is vital for monitoring the progression of PD. The current method of assessing bradykinesia requires patients to perform certain motor tasks in clinical settings. A Unified Parkinson Disease Rating Scale (UPDRS) score is assigned to each task based on the observation by a physician. However, PD patients do not always show natural symptoms during a clinical visit. Also, subjective bias occurs during such assessment of bradykinesia [2]. To overcome these limitations, several attempts have been made to quantify bradykinesia using wearable sensors [3]. Accelerometer, gyroscope or a combination of both have been employed for acquisition of movement data to evaluate bradykinesia [3]. Time domain parameters derived from sensor signals for characterizing bradykinesia which includes speed, amplitude, hesitations, and halt have been evaluated in previous studies. However, the effect of frequency domain parameters and non-linear features extracted from sensor signals for evaluating the severity of bradykinesia is unknown. Whether or not it leads to an improvement in the assessment of bradykinesia needs to be investigated. It is known that the patients suffering from severe bradykinesia have their movement signal distorted due to unpredictable movement or hesitation. Nonlinear features can characterize the degree of complexity and provide further relevant insights regarding the severity of bradykinesia. In this study, we investigated the efficacy of various frequency-domain and nonlinear parameters to quantify bradykinesia. The objective was to develop a predictive model based on a combination of sophisticated linear (frequency) and non-linear features derived from the sensor signal which has not been previously explored in the literature.

Autism is a developmental disorder characterized by atypical social interactions and repetitive behaviors/restricted interests[1]. It is found that children with autism also experience delayed or impaired motor skills development [2]. It would be advantageous to develop methods that precisely evaluate these motor skills impairments. The use of robots for evaluating upper limb motor competency have been looked at in the stroke literature [3]. We would like to leverage robotic tools for motor skills assessment but with focus for children with autism spectrum disorder. Robotic methodologies provide a unique way of testing upper limb motor skills. For instance, if a person holds on to the end of a robot arm and moves the robot arm in space, the robot can apply forces and prevent or assist the person with these motions. In this fashion, the robot can apply perturbations in a repeatable and precise manner with high fidelity. Since individuals with autism have anxieties interacting with other individuals[4], using an impersonal robot would alleviate the anxiety of social interactions. These individuals learn motor skills best with consistent repetition and strong reinforcement, qualities that robots provide. Therefore, a robot based evaluation strategy and therapy paradigm for children with Autism would be beneficial for the community.

Peripheral neuropathy (PN), commonly caused by diabetes mellitus, is a debilitating condition that currently affects approximately 20 million Americans. Chronic symptoms of PN often involve pain and weakness of the lower limbs, with eventual sensation loss on the plantar surfaces of the feet. According to epidemiological studies, reduced foot sole sensation has been linked to decreased standing stability [1] and an increased risk of falling [2]. Consequently, cost-effective interventions are needed to improve balance and mobility in this population. A growing body of research suggests that vibrotactile cues delivered to sensate areas of the lower limb may be an effective way to provide information about foot sole pressure to PN patients who experience poor balance control. Indeed, sensory substitution devices that provide vibrotactile feedback have been shown to aid in balance and improve postural control in various patient populations [3–7]. However, none of these technologies have been based on measurements of foot pressure nor have they been used as a balance prosthesis. The goal of this study was to investigate the effect of a new external lower-limb sensory prosthesis, the Walkasins™, on the balance and gait of individuals with PN who experience balance problems [8]. Walkasins™ consist of two parts: a leg unit and a foot pad (Figure 1). The leg unit wraps around the lower leg of the user and contains electronics for reading foot pad pressure signals, a microprocessor, and four vibrating motors that provide gentle tactile sensory cues to the front, back, medial, and lateral surfaces of the user’s leg. These cues reflect real-time foot pressure information at a location above the ankle where skin sensation is still present. The leg unit has a power button, two status LEDs, and a reset button (not shown in Figure 1). Power is supplied by a rechargeable internal battery. The foot pad is a thin consumable sole insert that can be cut to size and fit into a regular shoe. The foot pad connects to the leg unit through a physical cable. In this study, subjects performed gait and balance assessments with and without the Walkasins™ turned on in order to determine its short-term effects.

Ventricular assist devices (VADs) have become an accepted method of treating end-stage heart failure over the last few decades. In recent years, the use of rotary blood pumps (RBPs) as continuous flow VADs has surged ahead, and virtually eliminated the use of pulsatile-flow or volume-displacement pumps for implantable, chronic mechanical circulatory support (MCS). As the use of RBPs has become commonplace for the treatment of end-stage heart failure, the need for an implantable right-side MCS device for adults [1] and implantable MCS for the pediatric population has increased. Development of an implantable device specific to these populations includes unique challenges of anatomic placement and fixation. Computational Fluid Dynamics (CFD) is the use of numerical methods and algorithms to solve and analyze problems involving fluid flow. CFD has become a standard tool when designing RBPs, as it can calculate pressure-flow characteristics for a given rotary impeller speed. Additionally, through calculation of shear forces, CFD can also predict hemocompatibility by means of constitutive equations derived from empirical data. Particle image velocimetry (PIV), also known as flow visualization, is an optical measurement technique used to obtain velocity in fluids, which can be employed experimentally to verify CFD-based predictions of flow field. PIV also permits more rapid investigation of the RBP operativing range and transient conditions than can be achieved with CFD due to computational requirements. We have developed a RBP platform for chronic use with CFD to optimize hemodynamic performance. The miniaturized device includes unique inlet geometry with a rotating impeller and a vaned-diffuser in a 7mm axial hydraulic diameter. The design scheme separates the bearing and motor region from the primary flow path to further improve hemocompatibility and reduce the pump size without compromising the hydraulic capacity. Here we report CFD and PIV results of our device geometry optimized for right-sided MCS.

Minimally invasive surgery (MIS), including laparoscopy, endoscopy and colonoscopy, refers to performance of diagnostic or surgical intervention in the internal body cavity through small incisions (or no incisions) to reduce the recovery time and minimize scarring [1]. It has gained worldwide popularity since the first report of laparoscopic cholecystectomy in the mid-1980s due to lower complications, cosmetic benefits and quick recovery [2] and has grown to include robotic approaches. One of the main challenges for this type of surgery is to provide sufficient real-time visual feedback using cameras. To address issues of narrow visual field and limited workspace in surgical visual feedback, existing devices may use onboard motors to provide pan and tilt orientation for the camera [3, 4], which makes the system bulky and expensive. (Here we draw a distinction from wire-driven steerable laparoscopes and constrain the discussion to robotic devices.) In this paper, we present a novel camera system with a parallel structure and elastic platform which has three active degrees of freedom (DOFs) to increase the visual field and implement a mechanical zoom function. This camera head can be mounted on various surgical robots (e.g. [5]) or can be inserted as a standalone device. The novelty of this device lies in its elastic platform, and the authors are unaware of this type of design or its kinematic analysis being presented previously.

Endoscopic nasal surgery is with minimal invasiveness for the surgical treatment of nasal disease. During traditional functional endoscopic sinus surgery (FESS), the surgeon uses one hand to hold the surgical instrument leaving the other hand to hold the endoscope. When the surgeon needs to use two hands to perform some complex procedure, an assistant surgeon is required to help holding the endoscope, and this requires good teamwork and long-time training. To solve this problem, researchers proposed to use robots to hold the endoscope, freeing the surgeon’s hands for bimanual operation. Sun developed a passive arm with pneumatic locking mechanism to hold the endoscope in FESS, but the surgeon needs to adjust the pose of the endoscope manually, which interrupts the surgery flow and lengthens the surgery time [1]. Many motor-driven endoscope holders have been proposed in literature [2], the surgeon interact with the robot with joystick, voice command, pedals or head movement [3–5]. However, there exists some drawbacks with these interacting methods, for example, joystick requires one of the surgeon’s hands, voice command is usually subject to interference and has long time-delay, foot pedals and head movement distract surgeon’s attention. Lin used a foot-attached IMU sensor to control an active robotic endoscopic holder, the inversion/eversion and abduction/adduction motions of foot are used to select and control different joints, but the motor can be only selected in order, which is unhandy for the four-joint scenario [6]. In this paper, a similar foot-attached IMU sensor is used, and the joints are selected in an easier manner, based on the angle of plantarflexion. Rather than the angle, the angular velocity of abduction/adduction is utilized to control the moving direction of the active joint. This paper describes the test result of the proposed control interface.

Natural orifice transluminal endoscopic surgery (NOTES) is a method in which tools are passed through a natural orifice to the surgical site. This removes the need for external incisions, which can allow patients to recover more quickly without any visible abdominal scarring. This surgical method also has several limitations including limited space, complex lumen geography, and difficult visualization [1]. To address these problems, researchers have developed various tools, including endoscope-based robots [2], and insertable bimanual robots [3]. However, some of the aforementioned constraints/limitations remain, and consideration of accessories for use with these tools remains relevant. Our lab designed a multifunctional NOTES robot, which consists of a snakelike linkage driven by cables that are attached to motors in an external housing to navigate through the lumen geometry; it also includes a bimanual end effector with interchangeable tool tips [4]. This paper introduces the design of an adjustable table mount to address the limitations related to transluminal insertion. It provides four passive degrees of freedom (DOFs) to grossly place the robot, and enables the robot to be fixed on surgical tables with different sizes. Benchtop testing on a surgical table with a patient mannequin demonstrates its functionality.

In human walking, the ankle plays an important role of supplying power needed for the forward motion [1]. However, traditional transtibial (TT, a.k.a. below-knee, BK) prostheses are passive, lacking the ability of generating power output in the prosthetic ankle. Consequently, amputees fitted with such prostheses suffer from multiple issues (asymmetric gait, greater metabolic energy expenditure, etc.). To address such issues, researchers have explored various technical approaches to develop powered TT prostheses. Hydraulics and pneumatics have been attempted, leveraging the high power density with these actuators (e.g. [2]). Electromagnetic actuators were used more extensively with its technological maturity and convenience in packaging. Typical examples include the multiple prototypes developed by the MIT Biomechatronics Group (e.g., [3]), the SPARKy project, and the Vanderbilt Transtibial Prosthesis. The TT prostheses mentioned above all include powered ankle joints to provide power for the users’ locomotion. However, cost and complexity are often given lower priority than performance in the development of such devices. Powered TT prosthesis is a typical low-volume product from a commercial perspective, and the resulting high cost is a major hurdle for the large-scale adoption among amputee users. General robotic components (motors, gearsets, etc.), in contrary, are produced in large quantities with relatively low prices. Such contrast is the major inspiration for this work: the goal is to develop a modular powered TT prosthesis based on low-cost commercial robotic components while minimizing the complexity in manufacturing and assembly.

Upper-limb motor impairment is caused by a wide variety of diseases, including Duchenne muscular dystrophy (DMD), stroke, and arthrogryposis multiplex congenita [1,2]. The resultant arm dysfunction can cause the patient to be incapable of many daily tasks, and therefore increasingly reliant on others for their care. Since many of the underlying diseases are either chronic or incurable, some current therapeutics take the form of orthotic devices that assist upper limb function, thereby improving patient quality of life [1]. One such example is the Wilmington Robotic Exoskeleton (WREX), consisting of a set of gravity-counterbalancing exoskeleton arms attached to either a full upper-body brace, or in previous models, a wheelchair [1]. This device and its successors have proven to be significant aids in allowing patients to perform everyday tasks such as eating and writing [1]. However, according to both patients and physicians, this device and others, while effective, are often underutilized due to factors including brace size and weight, low device comfort, unappealing brace aesthetics, low range of motion, and lack of brace adjustability. In order to increase patient utilization of exoskeleton arm systems, we thus propose the replacement of the current brace system with a novel vest device, designed specifically for increased patient comfort, device adjustability, aesthetics, and range of motion, while preserving the existing strength and durability of current solutions.

Spasticity is a common consequence of the upper motor neuron syndrome and usually associated with brain lesion, stroke, cerebral palsy, spinal cord injury, and etc. On the other hand, rigidity is a neuromuscular disorder often found in Parkinson’s disease patients. Both of spasticity and rigidity are characterized by abnormal hypertonic muscle behaviors that will cause discomfort and hinder daily activities. Worldwide, the estimated affected population of spasticity is around 12 million [1], and rigidity affects more than 10 million people [2]. Clinical evaluation of spasticity or rigidity involves personal assessment using qualitative scales, such as the Modified Ashworth Scale (MAS) or Modified Tardieu Scale (MTS) for spasticity and Unified Parkinson’s Disease Rating Scale (UPDRS) for rigidity. However, this evaluation method heavily relies on the rater’s personal experience/interpretation and usually results in poor consistency and low reliability. The goal of this design was to develop a quantitative measurement device that can be used to assist clinical evaluation of spasticity or rigidity. This portable device, the Position, Velocity, and Resistance Meter (PVRM), can be strapped around a patient’s limb to measure angular position, angular velocity and muscle resistance of a given joint while the patient’s limb is passively stretched by the clinician. Acquiring this quantitative data from patients will not only allow clinicians to make more reliable assessments but also help researchers gain additional insights into the quantification of spasticity and rigidity.