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The flexible ankle joint dorsiflexion assists orthotic component is one of the components in the jointed ankle-foot orthosis (AFO) which is used to assist patients with drop foot abnormalities. The total cost of fabricating the jointed AFO is still expensive because there is no local manufacturer for this flexible joint component, so they are still switching to imported components. Reverse engineering is carried out on the most widely used imported components so that they can be redesigned and manufactured with 3D printing technology. Design optimization begins with finite element analysis to observe material and given dorsiflexor moments of the component. Furthermore, a design of geometric shapes that can be modified is built so that: (1) can adjust the magnitude of the given dorsiflexor moment and (2) adjust to the material used during 3D printing fabrication. [ABSTRACT FROM AUTHOR]

An Ankle Foot Orthosis (AFO) is a device that supports the ankle joint to help improve gait. When fitting AFOs, clinicians tune the AFO, and the success of the tuning is often determined by observation, e.g. of a patient walking up and down a corridor. As a result, clinicians do not get a true picture of the patient's gait, therefore this study investigates the use of Inertial Measurement Units (IMU) for gait analysis. The aim is to provide clinicians with quantitative data about the patient's gait in real-world situations, helping them to determine how well the AFOs are performing. In this study, data were collected from one adult volunteer who was a regular wearer of two AFOs. The volunteer performed a series of activities while wearing the AFOs with different heel wedge heights and also while not wearing the AFOs. Data were collected from six IMU sensors but only the data from the shank sensors was used to perform gait analysis. The results from the gait analysis show that the IMU is sensitive to changes in angle- and time-based metrics whilst the volunteer was and was not wearing AFOs. This paper proposes a novel metric called negative momentum, which captures the continual progression of the shank forward which can be an indicator to show if the AFO is tuned correctly. This study suggests that two shank-mounted IMUs can be sufficient to perform gait analysis without the need of a full gait analysis lab. [ABSTRACT FROM AUTHOR]

For a patient suffering from a problem in the Ankle joint to regain healthy movement, a well-designed lower limb Orthosis AFO is required. This research aims to improve the movement of Orthosis through the design of an ankle joint that can perform the desired move for functional use while remaining low-cost. The improvement focuses on creating a new orthosis ankle joint mechanism using a pre-existing Actuator. This entails simulating normal foot function while also enhancing the range of motion of the Ankle joint. Specific requirements must be met in this study, such as the new proposed Ankle joint ability to flex up to 900 with the sagittal plane and be strong enough to support the patient body weight. Every component of the Ankle joint was designed using Solid Works software. After that, each component will be assembled, and the mechanism of the ankle joint mechanism will be simulated to visualize the imagined motion of the new Ankle joint model. The materials utilized (Inconel 718) were chosen after considering each material's cost, safety factor, and quality. The proposed Ankle joint was tested using the ANSYS software (Finite element analysis), and the results were examined to detect if the model could bear specified applied loads. The outcomes were examined, and the novel model proposed by this study was appraised. [ABSTRACT FROM AUTHOR]

The control technique for Lower Limb Rehabilitation Robot (LLRR) is complicated and requires the consideration of numerous internal and external elements. This paper presents the controller design of a lower limb Knee-Ankle-Foot Orthosis (KAFO) rehabilitation robot to restore mobility and assist Spinal Cord Injury (SCI) and brain stroke Patients. The framework of the KAFO system is made of two Degree-Of-Freedom (DOF) for the knee and ankle joints. In this study, the nonlinear differential equations have been linearized using Jacobean's method. Then, the feedback linearization method is used to facilitate the controller design. The Computed Torque Control (CTC) based on PD (CTC-PD) has been developed based on PD control (CTC-PD). A comparison with an optimal state feedback control strategy of Linear Quadratic Regulator (LQR) control has also been carried out using the linearized system model. The comparison is carried out based on evaluating the Root Mean Square Error (RMSE) function. Meanwhile, the Particle Swarm Optimization (PSO) algorithm has been implemented in order to further improve the gain values for the implemented controller. Finally, simulation results have revealed that the CTC-PD controller can give reliable estimations and control, where the CTC-PD RMSE has improved by 99.9% than LQR for the first link and second link. Besides, the CTC-PD method has claimed to reduce external disturbance and random noise and it is the most effective when compared to the LQR controller. [ABSTRACT FROM AUTHOR]

Sloped walking is commonly known to be benefited to health. However, the increase of GRF that contribute to increment to JRF during inclined walking compared to level-ground walking also has been a concern in preventing injury. Therefore, the aim of this study was to assess the effect of sloped walking in comparison with level-ground walking to GRF and JRF at hip, knee and ankle joints. Ten healthy male participants (age: 24 ± 1.2 years old with normal body mass index (BMI)) were asked to walk at preferred speed on customized ramp at the slopes of -5°, 0° and 5°. Kinematic data were captured with five-camera motion capture system (Qualysis Track Motion). Kinetic data were measured with two force plate (Bertex) which embedded into the ramp. A musculoskeletal model (Visual 3D C-motion) was used to assess joint reaction force (JRF) of lower limb. Result show that peak value of mean GRF as well as maximum JRF at all joints of lower limb were higher during sloped walking compared to level-ground walking. In addition, the maximum JRF at hip is the highest, followed by knee and ankle for all walking conditions. GRF had a significant influence to the JRF at lower limb during inclined and declined walking where sloped walking have a higher force at all joints of lower limb than level- ground walking. Therefore, a suitable walking strategy in adapting the forces demand is required in preventing any slope slippage and/or vertical body instability that might lead to musculoskeletal injury. [ABSTRACT FROM AUTHOR]

External shock-wave loading is used in therapeutic dosages for the prevention and treatment of fractures. Features of a patient's physiological condition (age, illness, injury) require an individual choice of the parameters of low-energy acoustic (mechanical) action. This paper presents the results of modeling an external shock-wave loading of varying intensity in the areas of the femoral, knee, and ankle joints of real geometry. The simulation results showed that the range of permissible loads that do not lead to degradation of bone tissue, depending on the geometry of the bone, should be selected with taking into account the area of acoustic exposure. The safest is low-intensity exposure. [ABSTRACT FROM AUTHOR]

This work presents a description of the EXOSMOOTH project, oriented to the benchmarking of lower limb exoskeletons performance. In the field of assisted walking by powered lower limb exoskeletons, the EXOSMOOTH project proposes an experiment that targets two scientific questions. The first question is related to the effectiveness of a novel control strategy for smooth assistance. Current assist strategies are based on controllers that switch the assistance level based on the gait segmentation provided by a finite state machine. The proposed strategy aims at managing phase transitions to provide a smoother assistance to the user, thus increasing the device transparency and comfort for the user. The second question is the role of the actuation at the ankle joint in assisted walking. Many novel exoskeletons devised for industrial applications do not feature an actuated ankle joint. In the EXOSMOOTH project, the ankle joint actuation will be one experimental factor to have a direct assessment of the role of an actuated joint in assisted walking. Preliminary results of 15 healthy subjects walking at different speeds while wearing a lower limb exoskeleton supported the rationale behind this question: having an actuated ankle joint could potentially reduce the torques applied by the user by a maximum value of 85 Nm. The two aforementioned questions will be investigated in a protocol that includes walking on a treadmill and on flat ground, with or without slope, and with a load applied on the back. In addition, the interaction forces measured at the exoskeleton harnesses will be used to assess the comfort of the user and the effectiveness of the control strategy to improve transparency. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to measure the passive mechanical resistance torque in ankle braces. It highlights the application of lace-up style ankle braces, which is one of the most commonly used to prevent ankle ligament injuries. Findings of the study identify the passive mechanical resistance torque around the plantar-dorsi flexion (PF) axis and specify the different torque generated by each brace over the entire range of motion.