Load Sensor Research Articles

Interaction Motion Control on Tri-finger Pneumatic Grasper using Variable Convergence Rate Prescribed Performance Impedance Control with Pressure-based Force Estimator

Pneumatic robot is a fluid dynamic based robot system which possesses immense uncertainties and nonlinearities over its electrical driven counterpart. Requirement for dynamic motion handling further challenged the implemented control system on both aspects of interaction and compliance control. This study especially set to counter the unstable and inadaptable proportional motions of pneumatic robot grasper towards its environment through the employment of Variable Convergence Rate Prescribed Performance Impedance Control (VPPIC) with pressure-based force estimation (PFE). Impedance control was derived for a single finger of Tri-finger Pneumatic Grasper (TPG) robot, with improvement being subsequently made to the controller’s output by appropriation of formulated finite-time prescribed performance control. Produced responses from exerted pressure of the maneuvered pneumatic piston were then recorded via derived PEE with adherence to both dynamics and geometry of the designated finger. Validation of the proposed method was proceeded on both circumstances of human hand as a blockage and ping-pong ball as methodical representation of a fragile object. Developed findings confirmed relatively uniform force sensing ability for both proposed PEE and load sensor as equipped to the robot’s fingertip with respect to the experimented thrusting and holding of a human hand. Sensing capacity of the estimator has also advanced beyond the fingertip to enclose its finger in entirety. Whereas stable interaction control at negligible oscillation has been exhibited from VPPIC against the standard impedance control towards gentle and compression-free handling of fragile objects. Overall positional tracking of the finger, thus, justified VPPIC as a robust mechanism for smooth operation amid and succeed direct object interaction, notwithstanding its transcendence beyond boundaries of the prescribed performance constraint.

133. Facet joint loading after one- and two-level cervical disc arthroplasty

133. Facet joint loading after one- and two-level cervical disc arthroplasty

LPG Mass Monitoring Scale with Automatic Gas Leakage Detector System

A crucial requirement used in everyday human life is the use of liquefied petroleum gas (LPG) or, more generally, cooking gas. However, problems arise for LPG users when the cooking process is disrupted due to running out of cooking gas without them realized that the volume of gas has reached a critical level. In addition, gas leaks may also occur which can cause the house fire. Therefore, this study aims to develop a product that can monitor the remaining volume of cooking gas content in a gas cylinder using a load sensor. The LPG weight value is through LCD display and LED from three different levels, which is green (full), yellow (medium), and red (critical) where it receives programming instructions from Arduino Uno. The product also performs a function of gas leak detector by using the MQ-2 gas sensor and the user will receive a notification warning about the gas leak via buzzer and SMS sent by ESP32. The development process for monitoring scale and gas leakage detector for liquid petroleum gas (LPG) is based on the adapted from the Engineering Design Process Model (EDP), which consists of five phases, namely identify the problem, gather information, select the best solution, develop model, testing and evaluation. The results show that the developed product able to functioning well. However, in terms of product design there is still room for improvement especially for the size of the product and the gas sensor position to make it more user friendly.

Smart Helmet using GSM GPS Technology

A motorcycle frequently called motorbike or two-wheelers, which is the most used than another form of automobiles because of its low price. But another side, this is the most unsafe automobile. The accident can happen for driving fast or drunk driving. Safety and security in vehicle traveling are a pre-eminent concern for all. With the rapid urbanization and staggering growth of transport networks like two-wheeler vehicles, safety on the roads and security on the bike has emerged as an inescapable priority for us. It has expanded the rate of accidents, which leads to several damages with loss of lives. In many circumstances, we cannot able to detect the accident's location. A helmet is a form of protecting gear worn to keep safe the head from injuries. More specifically, the helmet aids the skull in protecting the brain. A smart helmet can detect the accident's locations also save lives and makes two-wheeler driving safer from previously. This paper propounds a smart helmet system to avoid the accident. The system divides into three parts helmet circuit, automobile circuit, and mobile application. At first, the helmet circuit has IR and alcohol detection sensor. The automobile circuit has a 3-axis accelerometer, Bluetooth module, relay, and load sensor. The helmet circuit sends a signal to the automobile circuit to start if the helmet is wearied and no alcohol detects. Then the automobile circuit checks the status of the load to start. 3-axis accelerometer senses crash or hit. After detecting an accident mobile application sends the accident location automatically to police and emergency contact number via the database.

An Imaging Technique For Characterizing Viscoelasticity Of Drag-Reducing Solutions

Existing rheometric measurement techniques that use load and displacement sensors are unable to resolve the non-Newtonian features of dilute drag-reducing solutions. In the present investigation back-lit particle image velocimetry, or particle shadow velocimetry, was used to quantify the complex dynamics of these fluids in a novel flow geometry. The flow of three non-Newtonian solutions were investigated in a periodically constricted tube (PCT). The radius of the tube walls was sinusoidal with respect to the streamwise direction. The three fluids under consideration were aqueous solutions of a flexible polymer, rigid polymer and surfactant, all of which were previously shown to instill drag reduction in a high Reynolds number, turbulent channel flow. Three solutions with mass concentrations of 0.01%, 0.03% and 0.05% were considered for each additive. Steady shear viscosity measurements demonstrated that all rigid and flexible polymer solutions were noticeably shear-thinning, while the surfactant solutions had a water-like shear viscosity. Each solution was measured at five Reynolds numbers between approximately 1 and 100 within the PCT. Relative to Newtonian fluids within the PCT, the rigid polymer solutions produced a plug-like flow with a blunted velocity and attenuated vorticity at radial coordinate further from the tube centerline. The flexible polymer solution, known to have appreciable amounts of elasticity, demonstrated a distinct chevron shaped velocity contour, coupled with a negative vorticity pattern within the contraction regions of the PCT. Despite having a seemingly Newtonian shear viscosity, the surfactant solutions produced velocity and vorticity patterns reminiscent of the flexible polymer. The general implication is that surfactants share similar elastic traits as flexible polymers. The vorticity transport equation was used to derive distributions of the non-Newtonian torque, more commonly called the `polymer torque' in other literature. It was revealed that the non-Newtonian torque was the source of vorticity field disruption in the flows of flexible polymer and surfactant solutions.

Real-time assessment of anteroposterior stability of spinal segments

PurposeWhile anteroposterior instability of spinal segments is regarded as an important biomechanical aspect in the clinical evaluation of lumbar pathologies, the reliability of the available diagnostic tools is limited and an intraoperative method to quantify stability is lacking. The aim of this study was to develop and validate an instrument to measure the anteroposterior stability of a spinal segments in real-time.MethodsTorsi of five fresh-frozen human cadavers were used for this study. After pedicle screw insertion, a specifically modified reposition tool composed with load and linear sensors was used to measure the segmental anteroposterior motion caused by 100 N anterior and posterior force during 5 loading cycles on either side of the instrumentation by two different operators. The spinal segments were then resected from the torsi and anteroposterior loading with ± 100 N was repeated in an advanced biomechanical spine testing setup as a reference measurement. The Inter-correlation coefficient (ICC) was used for validation of the “intraoperative” device.ResultsInter-operator repeatability of the measurements showed an ICC of 0.93 (p < 0.0001) and the bilateral (left–right) comparison had an ICC of 0.73 (p < 0.0001). The ICC resulting from the comparison to the reference measurement was 0.82 (p < 0.0001) without offset correction, and 0.9 (p < 0.0001) with offset correction. The ICC converged at this value already after two of the five performed loading cycles.ConclusionAn accurate and reliable measurement tool is developed and validated for real-time quantification of anteroposterior stability of spinal segments and serves as a basis for future intraoperative use.

Improvising micro transactions using IOTA tangle on smart refrigerator applications

The world moves towards the concept of automation. Day to Day more number of people uses the creation of new technology in effective manner. This paper helps to design a smart refrigerator using IOTA. The load sensor fixed under the tray of the refrigerator senses the load of the tray. If the load decreases the IP camera fixed to the refrigerator captures the image of the items in the tray and sends it to the user’s registered email. The catalogue of products will be available via a mobile app, through which he/she will be able to purchase the items required by viewing the image of the refrigerator sent. The transactions will be performed through IOTA network. When micro transactions are performed in Block chain, it takes more time to approve the process. By using IOTA tangle, the transactions will be carried out more fast and more secure. Thus, the payment process implemented using IOTA tangle is more secure and effective. Finally, the list of items ordered by the users will be sent to the nearby grocery store and will be delivered to the customer at their door step.

Design and Development of SPM for Nut Sorting

Abstract: In the complex industrial environment, there are many interference objects when detecting the objects on the production line. The interference objects are very similar to the objects to be sorted in terms of colour, shape, and size. The existing detection methods like edge detection and object segmentation make it difficult to recognize the objects in the complex industrial environment. Detection of dimensions using load sensor, Infrared sensor, and Arduino program. The machine is controlled by Arduino (microcontroller) with a Servo motor. The aim of this project is the separate hexagonal nuts according to their dimension. These systems can be used in several applications aimed to automatize the process of sorting. With the help of this machine, work efficiency can be increased and labour can be decreased. The project's purpose is to create a Mechatronics system that can sort nuts. It would also be able to detect and reject other items in the process. The project's goal will be to supply the industry with a piece of working equipment for direct use in the Quality Control department at a minimal cost. Keywords: size, shape, hexagonal nut, quality control, infrared sensor, load sensor

Performance evaluation of PV powered solar tunnel dryer integrated with a mobile alert system for shrimp drying

The study was aimed at evaluating the drying characteristics, modelling of drying behaviour, and performance of PV powered walk-in-type semi-cylindrical forced convection solar tunnel dryer integrated with a mobile alert system using shrimps (Metapenaeus dobsoni). The dryer was fabricated using UV stabilized polythene film, CPVC pipes, and GI frames and coupled with a PV panel. A mobile alert system consisting of an Arduino UNO, load sensor, and GSM module was evaluated as an automatic data acquisition and information support system for the dryer users. Fresh shrimp samples were dried to the moisture content of 10.54% (w.b) from 79.22% (w.b) in 6 h. The graph of drying rate against the time exhibited that shrimp drying took place under the falling-rate drying period. Mathematical modelling of the drying process revealed that the Page model could accurately predict the drying behaviour of shrimp. The maximum drying efficiency of 20.22% was attained for drying shrimp in the solar tunnel dryer under forced convection. PV panel obtained an average electrical efficiency of 11.64% and supported the load requirement of 0.636 kWh/day for drying. The mobile alert system was effectively tested as an automatic data acquisition and information support system for dryer users.

Sensor Screening Methodology for Virtually Sensing Transmission Input Loads of a Wind Turbine Using Machine Learning Techniques and Drivetrain Simulations

The ongoing trend of building larger wind turbines (WT) to reach greater economies of scale is contributing to the reduction in cost of wind energy, as well as the increase in WT drivetrain input loads into uncharted territories. The resulting intensification of the load situation within the WT gearbox motivates the need to monitor WT transmission input loads. However, due to the high costs of direct measurement solutions, more economical solutions, such as virtual sensing of transmission input loads using stationary sensors mounted on the gearbox housing or other drivetrain locations, are of interest. As the number, type, and location of sensors needed for a virtual sensing solutions can vary considerably in cost, in this investigation, we aimed to identify optimal sensor locations for virtually sensing WT 6-degree of freedom (6-DOF) transmission input loads. Random forest (RF) models were designed and applied to a dataset containing simulated operational data of a Vestas V52 WT multibody simulation model undergoing simulated wind fields. The dataset contained the 6-DOF transmission input loads and signals from potential sensor locations covering deformations, misalignments, and rotational speeds at various drivetrain locations. The RF models were used to identify the sensor locations with the highest impact on accuracy of virtual load sensing following a known statistical test in order to prioritize and reduce the number of needed input signals. The performance of the models was assessed before and after reducing the number of input signals required. By allowing for a screening of sensors prior to real-world tests, the results demonstrate the high promise of the proposed method for optimizing the cost of future virtual WT transmission load sensors.

Change in Electrical Resistance of SMA (NiTi) Wires during Cyclic Stretching.

In this article, the use of Nickel Titanium (NiTi) alloy as a sensor is examined. A cyclic stretching test, that has various elongations (0.5 and 1%), is administered to NiTi wires with various diameters and lengths. It is assumed that the elongation enables an observation of the change in electrical resistance of the NiTi wires, due to martensite reorientation. During the test, the stretching force, the displacement, and the electrical resistance of the NiTi wires are measured. Following the test, the resistance of all the tested samples differed compared to the starting position. Conducted research indicates that NiTi wires are very sensitive to resistance change when they are deformed. A large difference in NiTi electrical resistance was visible in all samples during the first stretching cycle. For longer wires, with a smaller diameter, resistance change was visible during almost all of the stretching cycles. However, the observed changes were very small. Based on the obtained results, it can be justifiably stated that NiTi wires could be used to build deformation sensors, which operate both online and offline. Moreover, NiTi wires with a small diameter could be used to create cyclic loading sensors. Such sensors can be used in self-sensing applications or in structural health monitoring.

Development of a Handheld IoT-Based Fruit Harvester to support Agrotourism

Agrotourism, a development in the tourism industry that can increase the economic potential of an area, offers many activities, such as fruit picking tours. Fruit picking, a crucial part of the harvesting process, involves separating fruits from plants to obtain economic value. However, several common mistakes during harvesting can damage the plants or branches. In this study, we developed a mechanical fruit harvester incorporated with the Internet of Things (IoT). The harvester has multiple functions, such as minimizing the damage to tree branches, monitoring the fruit productivity of each plant, and providing information on fruit weight and prices in real-time. The tool is equipped with a smartphone, several infrared and load sensors, a microcontroller, a cloud data logger, and a data analysis system. We tested the accuracy of the GPS on several smartphones while in agrotourism areas. The accuracy of the GPS on the harvesting tool is approximately 3 meters, and the success rate in calculating the number of fruits using the infrared sensor is 93.3 %, depending on the diameter of the fruit passing into the bucket. In addition, the harvester is equipped with a load sensor with a measurement deviation rate of 2.48%.

Ultra high-resolution biomechanics suggest that substructures within insect mechanosensors decisively affect their sensitivity.

Insect load sensors, called campaniform sensilla (CS), measure strain changes within the cuticle of appendages. This mechanotransduction provides the neuromuscular system with feedback for posture and locomotion. Owing to their diverse morphology and arrangement, CS can encode different strain directions. We used nano-computed tomography and finite-element analysis to investigate how different CS morphologies within one location—the femoral CS field of the leg in the fruit fly Drosophila—interact under load. By investigating the influence of CS substructures' material properties during simulated limb displacement with naturalistic forces, we could show that CS substructures (i.e. socket and collar) influence strain distribution throughout the whole CS field. Altered socket and collar elastic moduli resulted in 5% relative differences in displacement, and the artificial removal of all sockets caused differences greater than 20% in cap displacement. Apparently, CS sockets support the distribution of distal strain to more proximal CS, while collars alter CS displacement more locally. Harder sockets can increase or decrease CS displacement depending on sensor location. Furthermore, high-resolution imaging revealed that sockets are interconnected in subcuticular rows. In summary, the sensitivity of individual CS is dependent on the configuration of other CS and their substructures.

Numerical and Experimental Investigation of the Effect of Micro Restriction Geometry on Gas Flows through a Micro Orifice

This study experimentally and numerically investigates the effects of the nozzle/needle distance (clearance) and supply pressure on single phase compressible gas flow in a micro orifice with needle restriction, which play important roles in many engineering applications such as cryogenic cooling and MEMS (microelectromechanical systems) device cooling. Nitrogen was used as the working fluid at supply pressures ranging from 10 to 50 bars, while the conical needle draft angle was 15°. The nozzle/needle distance (clearance) was changed from 100 µm to 500 µm. From the experimental point of view, the load provided by the working fluid over the needle was measured by a load sensor. For the numerical analysis, six turbulence models and three wall treatments were considered in numerical simulations. The effect of micro restriction on high-pressure micro-gas flows was further assessed by numerical modeling. It is evident from the results that the utilized turbulence model has a considerable effect on the computed results. The k–ε standard and Spalart–Allmaras models were found to be not suitable for modeling micro-scale gas flows with restriction. On the other hand, the k–ε realizable and k–ω SST models exhibit the best performance in predicting the results.

Efficient Energy Utilization Algorithm through Energy Harvesting for Heterogeneous Clustered Wireless Sensor Network

The usefulness of wireless sensor networks has fascinated the world’s attention. Usage of low-power microcontrollers and wireless sensors to handle real-world problems such as environmental, medicinal, and structural monitoring has exploded. Wireless sensor nodes are extremely tiny and are designed for low-duty applications such as recording physical characteristics. Wireless sensor network operations such as sensing, calculations, and communication take extensively more energy than these low-powered sensor nodes. They are used both in attainable and inaccessible areas and are usually powered by batteries. Since the sensor is powered by batteries, replacing and charging the battery after its depletion are challenging. Manual battery replacement is hampered by geographical restrictions, which results in significant reduction of wireless sensor network performance and longevity. As a result, this study addresses the energy-constrained wireless sensor networks by creating a technological model to a heterogeneous clustered wireless sensor network in an outdoor application using solar-enabled energy harvesting photovoltaic cells. Due to lack of energy, this effort was employed to overcome the challenges of relatively restricted processing performance and limited radio frequency transmission bandwidth. The program was created to efficiently utilize the energy produced from solar panels and charge the batteries in a variety of ways. The algorithm also controls the discharging process. According to the results of extensive investigation and experimentation, the sensor is continuously operated even when there is no solar light. The batteries are charged on bright day and discharged at night and on overcast days. The algorithm is used to govern the energy supplement to rechargeable lithium-ion polymer batteries as well as a load (sensor). In the worst scenario (no solar light/cloudy, and sensors reporting data every 30 minutes), the present cluster head sensor with 6 ordinary nodes in the cluster lasts just 16.6667 days. But the life duration of the newly designed model algorithm has been raised to 54.16667 days. The normal sensor node’s life duration has also been enhanced from 50 to 91.66667 days.

Experimental analysis of wave-induced vertical bending moment in steep regular waves

Recent studies have benchmarked the prediction of the wave vertical bending moment (VBM) of ships in waves and found significant scatter among the numerical codes. A long series of tests with segmented hulls have been reported in the literature over the past 70 years to assess the vertical bending moment. However, alongside the improvement in numerical tools and the modeling of ships’ internal loads, the scientific community still requires accurate experimental data measured in steep waves (ratio of wave height H to wavelength λ, H/λ= 0.1) where the ship behavior and loads are modified by non-linearities. Thus, in order to validate simulation codes, and to establish criteria and requirements that make ships safer to sail in severe sea conditions, some experiments were carried out in the 50 m × 30 m × 5 m hydrodynamic and ocean engineering tank of the Ecole Centrale Nantes. A 1/65th scaled model of a 6750-TEU containership was used. The ship was moored and several combinations of wavelength and wave height were tested. The present experiments were performed on a segmented hull with a 6DOF load sensor located close to amidship, where some measurements were available from previous studies. The design, which did not use strain gauges, was done specifically to increase the first structural mode frequency and the stiffness of the model in order to reduce and make it possible to filter out hydro-elastic effects. The model motion was measured through a Qualisys IR tracking system and accelerometers were located on the fore and aft of the beam. Also, each of the 9 segments is equipped with a 3DOF dynamometer to measure the hydrodynamic loads on the hull. A mathematical description of the relations between the hydrodynamic forces, the load measurements and the internal forces is given in the paper. This makes it possible to retrieve the hydrodynamic loads on the segments and then to compute the shear force and bending moment discretized at each intersegment all over the ship length. Particular care was paid to the reproducibility and repeatability of the tests. The experimental setup and the measured data are presented in the paper. Hydrodynamic loads are reconstructed and the obtained VBM is compared with the 6DOF sensor measurement. The non-linear effects of increasing the wave steepness on motions and bending moment are discussed.

In Vitro Comparison of Different Invisalign® and 3Shape® Attachment Shapes to Control Premolar Rotation.

Aim: To evaluate in vitro the differences of various Invisalign® attachments in their effectiveness during derotation of an upper second premolar in terms of forces and moments created and compare them to the 3Shape® box attachment as well as to no attachment at all. Materials and Methods: A Force System Identification (FSI) machine, comprising two load sensors, was used in this study. Sensor 1 was connected to the test tooth (i.e. upper second premolar) carrying a different attachment design, and the fixed sensor (Sensor 2) was connected to the base model. Once the corresponding aligner was passively seated on the teeth, 12 different setups (i.e. 11 different attachments and one setup with no attachment at all) were tested by rotating the test tooth 4.5° mesially and 4.5° distally, in increments of 0.45°. Results: The vertical rectangular attachments were able to generate the highest derotational moment on both mesial and distal rotations but also received the most side effects (intrusive force, torque, and tipping). The no-attachment setup performed least favorably in terms of derotational ability but exhibited the least side effects. In the y-axis, all attachments received a buccal root torque with a lingual force during disto-rotation and a lingual root torque with a buccal force during mesio-rotation. Conclusion: Attachments are necessary for derotating an upper second premolar. An aligner incremental change of more than 1° derotation can generate high moments. The vertical rectangular attachments perform best in derotations; however, they exhibit the most side effects. Finally, despite presenting the least side effects, derotation of a premolar with no attachment is not as efficient.

Longitudinal Control of Autonomous Vehicles Consisting Power-Train With Non-Linear Characteristics

The autonomous vehicle studiesrecently have been accelerated to ensure more secure, efficient, and comfortable transportation. Non-linearity in the power-train makes longitudinal control of autonomous vehicles difficult at low speeds. Additionally, rapid acceleration and deceleration (due to the behavior of the surrounding vehicles) increase complexity in control of such systems. In this study, we designed a novel longitudinal controller including the reverse plant model of the vehicle to overcome these problems. The complete controller is designed using parameters known to OEMs (Original Equipment Manufacturer) with vehicle CAN bus signals. The longitudinal controller consists of two parts: The outer controller which determines the target speed according to lead vehicle’s speed and the inner controller which determines the accelerator pedal percentage and brake requests. The inner controller includes PI followed by the reverse plant model with a virtual load sensor. This model enables control of a vehicle with non-linear power-train. The designed controller performance was tested on a city bus with a diesel engine and automatic transmission. Vehicle test results proved, that the designed controller is capable of controlling an autonomous vehicle with nonlinear power-train dynamics with onboard computational capacity even at low speeds.

Intraoperative Load Sensing in Total Knee Arthroplasty Leads to a Functional but Not Clinical Difference: A Comparative, Gait Analysis Evaluation.

Introduction: Although Total Knee Arthroplasty (TKA) is a successful procedure, a significant number of patients are still unsatisfied, reporting instability at the mid-flexion range (Mid-Flexion Instability-MFI). To avoid this complication, many innovations, including load sensors (LS), have been introduced. The intraoperative use of LS may facilitate the balance of the knee during the entire range of motion to avoid MFI postoperatively. The objective of this study was to perform a Gait Analysis (GA) evaluation of a series of patients who underwent primary TKA using a single LS technology. Methods: The authors matched and compared two groups of patients treated with the same posterior stabilized TKA design. In Group A, 10 knees were intraoperatively balanced with LS technology, while 10 knees (Group B) underwent standard TKA. The correct TKA alignment was preoperatively determined aiming for a mechanical alignment. Clinical evaluation was performed according to the WOMAC, Knee Society Score (KSS) and Forgotten Joint Score, while functional evaluation was performed using a state-of-the-art GA platform. Results: We reported excellent clinical results in both groups without any statistical difference in patient reported outcome measurements (PROMs); from a functional standpoint, several GA space–time parameters were closer to normal in the sensor group when compared to the standard group, but a statistically significant difference was not reached. Conclusions: Gait Analysis represents a valid method to evaluate TKA kinematics. This study, with its limitations, showed that pressure sensitive technology represents a valid aid for surgeons aiming to improve the postoperative stability of TKA; however, other factors (i.e., level of intra-articular constraint and alignment) may play a major role in reproducing the normal knee biomechanics.

Analysis and experimental study of oil well indicator diagram based on electric parameter method

At present, the load diagram of pumping wells mostly uses load sensors to obtain load data. However, the load sensor is prone to mechanical fatigue during the measurement process, which results in measurement data drift distortion and large errors. This paper presents an electrical parameter measurement method to improve this problem. The electrical indicator diagram is obtained by measuring the instantaneous input power of the driving motor of the pumping unit, calculating the transmission loss in real time, and establishing the mathematical model of the polished rod load and displacement of the pumping unit. The correctness and effectiveness of the electrical indicator diagram were verified by field experiments.