Tibiofemoral dynamic stressed gap laxities correlate with compartment load measurements in robotic arm-assisted total knee arthroplasty

Aims It is unknown whether gap laxities measured in robotic arm-assisted total knee arthroplasty (TKA) correlate to load sensor measurements. The aim of this study was to determine whether symmetry of the maximum medial and lateral gaps in extension and flexion was predictive of knee balance in extension and flexion respectively using different maximum thresholds of intercompartmental load difference (ICLD) to define balance. Methods A prospective cohort study of 165 patients undergoing functionally-aligned TKA was performed (176 TKAs). With trial components in situ, medial and lateral extension and flexion gaps were measured using robotic navigation while applying valgus and varus forces. The ICLD between medial and lateral compartments was measured in extension and flexion with the load sensor. The null hypothesis was that stressed gap symmetry would not correlate directly with sensor-defined soft tissue balance. Results In TKAs with a stressed medial-lateral gap difference of ≤1 mm, 147 (89%) had an ICLD of ≤15 lb in extension, and 112 (84%) had an ICLD of ≤ 15 lb in flexion; 157 (95%) had an ICLD ≤ 30 lb in extension, and 126 (94%) had an ICLD ≤ 30 lb in flexion; and 165 (100%) had an ICLD ≤ 60 lb in extension, and 133 (99%) had an ICLD ≤ 60 lb in flexion. With a 0 mm difference between the medial and lateral stressed gaps, 103 (91%) of TKA had an ICLD ≤ 15 lb in extension, decreasing to 155 (88%) when the difference between the medial and lateral stressed extension gaps increased to ± 3 mm. In flexion, 47 (77%) had an ICLD ≤ 15 lb with a medial-lateral gap difference of 0 mm, increasing to 147 (84%) at ± 3 mm. Conclusion This study found a strong relationship between intercompartmental loads and gap symmetry in extension and flexion measured with prostheses in situ. The results suggest that ICLD and medial-lateral gap difference provide similar assessment of soft-tissue balance in robotic arm-assisted TKA. Cite this article: Bone Jt Open 2021;2(11):974–980.

Plate Dampers in the Tensioning Plate Dampers in the Tensioning

The article analyses strengths and weaknesses of bandsaw machines. While analysing we have found the relationship between the weaknesses and the tension of a band saw. Its use as a cutting tool leads to a decrease in the lateral rigidity and stability of the cutting section on the pulling chain. This leads to fluctuations in the cutting width, a decrease in the geometric accuracy of sawn timber and an increase in the roughness of the side surfaces of a kirf. The main types of tensioning unit mechanisms, which strengthen the tension and maintain its stability during operation, are defined, and common design flaws are described. Oil-filled metal plate dampers promote space-saving and low-inertia dampers for bandsaw machines with any basic saw blade tensioning mechanisms. The influence of the device on the level of dynamic fluctuations of the tensile force caused by the artificial eccentricity of the tension pulley was studied. The efficiency was evaluated by computer oscillography of the tensile load sensor signal and subsequent computer processing of the obtained oscillograms. The effectiveness of using damper devices is confirmed by the quality of sawing, which is characterized by a lower level of roughness of the lateral surfaces of the cut while reducing the variation in thickness of a workpiece. Methods of eliminating flaws with different types of tensioning units are reviewed, and the effectiveness of using oil-filled plate dampers is evaluated. The article presents the research technique and parameters of the experimental unit as well as the conclusions on the effectiveness of damping devices. For citation: Alekseev A.E., Dumanskij I.O., Prokhorov A.V. Plate Dampers in the Tensioning Units of Bandsaw Machines. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 5, pp. 142–149. DOI: 10.37482/0536-1036-2021-5-142-149

DESIGN AND ANALYSIS OF ADVANCED WALKER CUM ROLLATOR

Over the year’s walker or rollator have helped many elderly people to overcome the barrier of dependency. As the age grows, the muscles and bones suffer weakening due to lack of calcium because of which person has to depend on others for their movement. This unwanted condition creates a bad physiological and psychological impact on the victim and slowly pulls them out of all possible types of interactions with society. Thus, to make the walker more users friendly, safe, and reliable, a new design or solution is proposed. This not only addresses the problem which is prevalent in the elderly section of society but also will be helpful to people with other disabilities. The proposed design of the walker is to increase the safety and movability of the user. The design of this walker is advanced as it consists of various sensors like an Obstacle sensor, GPS, and Load Sensor. In this paper, the design and analysis of an advanced walker cum rollator is elaborated, which significantly reduces the challenges faced by the elderly and specially challenged in day-to-day life.

Adapting Semi-Active Prostheses to Real-World Movements: Sensing and Controlling the Dynamic Mean Ankle Moment Arm with a Variable-Stiffness Foot on Ramps and Stairs

(1) Background: Semi-active prosthetic feet can provide adaptation in different circumstances, enabling greater function with less weight and complexity than fully powered prostheses. However, determining how to control semi-active devices is still a challenge. The dynamic mean ankle moment arm (DMAMA) provides a suitable biomechanical metric, as its simplicity matches that of a semi-active device. However, it is unknown how stiffness and locomotion modes affect DMAMA, which is necessary to create closed-loop controllers for semi-active devices. In this work, we develop a method to use only a prosthesis-embedded load sensor to measure DMAMA and classify locomotion modes, with the goal of achieving mode-dependent, closed-loop control of DMAMA using a variable-stiffness prosthesis. We study how stiffness and ground incline affect the DMAMA, and we establish the feasibility of classifying locomotion modes based exclusively on the load sensor. (2) Methods: Human subjects walked on level ground, ramps, and stairs while wearing a variable-stiffness prosthesis in low-, medium-, and high-stiffness settings. We computed DMAMA from sagittal load sensor data and prosthesis geometric measurements. We used linear mixed-effects models to determine subject-independent and subject-dependent sensitivity of DMAMA to incline and stiffness. We also used a machine learning model to classify locomotion modes using only the load sensor. (3) Results: We found a positive linear sensitivity of DMAMA to stiffness on ramps and level ground. Additionally, we found a positive linear sensitivity of DMAMA to ground slope in the low- and medium-stiffness conditions and a negative interaction effect between slope and stiffness. Considerable variability suggests that applications of DMAMA as a control input should look at the running average over several strides. To examine the efficacy of real-time DMAMA-based control systems, we used a machine learning model to classify locomotion modes using only the load sensor. The classifier achieved over 95% accuracy. (4) Conclusions: Based on these findings, DMAMA has potential for use as a closed-loop control input to adapt semi-active prostheses to different locomotion modes.

VIDEO RANCANGAN BY-PRO (SISTEM PENGUKURAN DAN PENDATAAN BALITA DI POSYANDU)

Integrated Healthcare Center (IHC) activity is important thing to do to make sure the toddlers health by measuring toddler's weight and height. Recently IHC activity is done by using manual measurement tools that is sometimes dangerous for the toddler, and it's quite troubled for IHC cadre in reporting and organizing data. It's needed in designing product that can support continuity of IHC activities so it can run safety and comfortably. This research will design a product BY-PRO, a main solution to solve the problems. The design consist of Arduino microcontroller as data processor, cell load sensor (weight), optocoupler modul (height), and censor K02 (touch sencor) connected to Android via modul (Bluetooth) HC-05. Android Application can be used by IHC cadre to show identity data and toddler measurement saved to database and distributed to web-based Information System to monitor realtime health by midwife. The design result is presented in a video, so it can give an overview of the designed product.Keywords— Toddler Height Measuring, Toddler Weight Measuring, Android, Arduino, Bluetooth, Website, Posyandu

E-Recycle Bin: An IoT Based Model for Solid Waste Management

This study focused on developing a Smart Bin Prototype by integrating Internet of Things(IoT) Technology in a Barangay Based Material Recovery Facilities (BBMRF) that is capable of printing a receipts based on the equivalent value of recyclable waste deposited in the bin which is called the e-Recycle Bin. The generated data from the e-Recycle Bin prototype is send in the clouds used by the web application to generate analytical report for monitoring purposes. This research used descriptive method and Rapid Application Development (RAD) methodology in developing the e-Recycle Bin prototype. This study explored the used IoT components namely, Rapsberry pi, Arduino Mega, SIM800 GSM Module, Straight Bar Load Sensor, Ultrasonic Sensor, IR Proximity Sensor, 2x4 LCD Monitor, and thermal printer. The IT experts evaluated the project and at overall weighted mean of 4.91 and a qualitative description of Very High Extent of compliance with ISO 25010:2015 Software Quality Requirements. This study sought the implementation of the developed system in the City of Ilagan to help mitigate solid waste problems and encourage waste recycling among the city residents.

Modeling Movement of Supports of Walking Machines with Dynamic Stability by Using a Stand

Introduction. Walking machines have been interesting for decades. Modern technologies make it possible to create new designs with digital control. Creating software that allows a walking machine to move independently is a difficult task. Walking machine onboard computer needs to process data from sensors in real time. The article demonstrates design and algorithms used to control the motion of an experimental walking machine. Materials and Methods. To simulate the motion of a walking machine and experimental studies, a stand replicating all the electronic systems of the machine was made. The order of rearrangement of the supports during the motion and the trajectory of the support movement are shown. The design of sensors and their principle of operation are considered. The simulation bench with a description of its electronic components is demonstrated. Results. The optimal parameters of the support motion are determined. A cyclic algorithm for specifying the motion of a support along a trajectory consisting of rectilinear segments is described. The problem of synchronization of motion of a set of supports using multithreaded asynchronous programming adapted for multidimensional processors has been solved. The process of lowering the support to the surface and the response of the cyclic algorithm to changes in the shock and load sensor readings are simulated. Discussion and Conclusion. An algorithm for propulsion with reaction to changes in sensor readings has been developed. The conducted research allowed us to obtain an optimal algorithmic model of motion, to which it is easy to add new reactions of the automatic motion control system based on sensor readings.

Identification of Gait-Cycle Phases for Prosthesis Control

The major problem with transfemoral prostheses is their capacity to compensate for the loss of the knee joint. The identification of gait-cycle phases plays an important role in the control of these prostheses. Such control is completely up to the patient in passive prostheses or partly facilitated by the prosthesis in semiactive prostheses. In both cases, the patient recovers his/her walking ability through a suitable rehabilitation procedure that aims at recreating proprioception in the patient. Understanding proprioception passes through the identification of conditions and parameters that make the patient aware of lower-limb body segments’ postures, and the recognition of the current gait-cycle phase/period is the first step of this awareness. Here, a proposal is presented for the identification of the gait-cycle phases/periods under different walking conditions together with a control logic for a possible active/semiactive prosthesis. The proposal is based on the detection of different gait-cycle events as well as on different walking conditions through a load sensor, which is implemented by analyzing the variations in some gait parameters. The validation of the proposed method is done by using gait-cycle data present in the literature. The proposal assumes the prosthesis is equipped with an energy-storing foot without mobility.