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The force sensing is used in robotic assembly tasks. The sensors developed are much advanced and costly. The force transducers are generally configured and deployed at the wrist of the robotic arm. The purpose of this paper is to describe the concept of an elastic transducer to make available cost-effective force sensor with simple construction and analysis.

The analytical formulation is developed herewith for one-, two- and three-axis elastic cantilever configuration. The force to be measured can be calculated analytically using derived strain expressions. The strains are estimated using proposed formulation, further crosschecked through FEA approach. The analytical method for strain estimation using moment equations is presented along with validation using finite element method (FEM) tool (ANSYS 15.0) with the case study.

The derivation of expressions for force components from strains is developed. The resulting formulation found to confirm the estimated strains from analytical methods closely to the FEM results. Theoretically, it is possible to find contact forces and angle of force on stationary force platform. It is found that the magnitude of estimated contact forces is within 1 per cent deviations.

The mathematical modeling and FEA simulation of the three-axis force sensor under elastic (no deformation) conditions.

These sensors are ranging from simple crossbar structure to Stewart platform type. The subsequent development in this field pertains to performance enhancement such as accuracy and cross-sensitivity. The basic structure of the sensor has not changed drastically. The major problem, as discussed by many authors, is a complex interdependence of six components and intricate geometrical structure. Derivation of expressions for force components from strains is a breakthrough contribution by the authors. The analytical treatment for finding the strains is aimed in this paper.

One of the major shortcomings in the data process of the traditional wheel force transducers (WFTs) is the theoretical errors of initial value determination. A new method to identify the initial values of the WFT for the solution of this problem is proposed in this paper. The paper aims to discuss these issues.

With this method, the initial values can be obtained by equations which are established based on multiple stops on horizontal road.

The calibration and contrast tests on the MTS calibration platform illustrate the better performance with the new method. Moreover, the real vehicle test confirms the effectiveness in practice.

The test results show that the new method of initial calibration has an advanced performance compared to the traditional one. In addition, it is effective in the brake test with a real vehicle.

Describes the processes required for the selection of the correct force/torque sensor system for a robot end effector. Covers six axis force/torque sensors and methods for interfacing them to computers and the robot’s control system.

This paper seeks to present an acceleration‐based force‐impedance controller, applied to a six‐dof parallel mini‐manipulator: the robotic controlled impedance device (RCID).

The proposed control strategy involves three cascade controllers: an inner acceleration controller, built as a set of six single input/single output acceleration controllers (one per manipulator axis), an impedance task‐space controller, and an outer force controller.

The control strategy enables two kinds of manipulator behaviour: force‐limited impedance control and position‐limited force control. The type of behaviour depends only on the chosen manipulator trajectories.

The RCID may be used as a force‐impedance controlled auxiliary device, coupled in series with a position‐controlled commercial industrial robot. The two manipulators combined behave as a single manipulator, having the impedance and force control performance of the RCID, as well as the workspace and trajectory tracking performance of the industrial manipulator. The industrial manipulator should perform free space motion trajectory tracking, the RCID being kept in a “home” position, preserving its small workspace for impedance and force control.

A robust control strategy that enables good performance, while the robot executes tasks that involve interaction with the environment, is being proposed. Experimental results on a force‐impedance controlled six‐dof parallel mini‐manipulator are presented.

Microsyn signal generators have been used in high-precision inertial sensors for their good structural stiffness and high sensitivity. However, as the stator and the rotor of the microsyn are both constructed of silicon-steel laminations with high permeability, an extremely small non-concentricity between the stator and rotor of microsyn will cause two random reaction torques acting on the output axis. As a result, difficulty arises in compensating for these random reaction torques. This study aims to investigate the electromagnetic fields of a novel angular transducer characterized by high sensitivity.

Based on the operation principles of the new transducer, the output voltage is decided by the time rate of change of the net magnetic flux of each output pole. The transient analysis of the electromagnetic field of the transducer is carried out by ANSYS Maxwell-3D.

The distributions of the magnetic flux of the transducer’s interior and eddy current on the rotor are consistent with the results of theory analysis. Moreover, the leakage flux mainly distributes nearby the excitation poles. The novel small-angle transducer also possesses a remarkably low reaction torque and power loss.

Study on the electromagnetic fields of the new transducer not only provides a powerful basis to further improve the precision of the new transducer but also expands the scope of applications of the new transducer.

This new transducer is not only characterized by a high sensitivity, high linearity and fast response but also extremely low reaction torque and power losses. Thus, the new transducer is suitable for high-precision inertial sensors.

Plantar force is the interface pressure existing between the foot plantar surface and the shoe sole during static or dynamic gait. Plantar force derived from gait and posture plays a critical role for rehabilitation, footwear design, clinical diagnostics and sports activities, and so on. This paper aims to review plantar force measurement technologies based on piezoelectric materials, which can make the reader understand preliminary works systematically and provide convenience for researchers to further study.

The review introduces working principle of piezoelectric sensor, structures and hardware design of plantar force measurement systems based on piezoelectric materials. The structures of sensors in plantar force measurement systems can be divided into four kinds, including monolayered sensor, multilayered sensor, tri-axial sensor and other sensor. The previous studies about plantar force measurement system based on piezoelectric technology are reviewed in detail, and their characteristics and performances are compared.

A good deal of measurement technologies have been studied by researchers to detect and analyze the plantar force. Among these measurement technologies, taking advantage of easy fabrication and high sensitivity, piezoelectric sensor is an ideal candidate sensing element. However, the number and arrangement of the sensors will influence the characteristics and performances of plantar force measurement systems. Therefore, it is necessary to further study plantar force measurement system for better performances.

So far, many plantar force measurement systems have been proposed, and several reviews already introduced plantar force measurement systems in the aspect of types of pressure sensors, experimental setups for foot pressure measurement analysis and the technologies used in plantar shear stress measurements. However, this paper reviews plantar force measurement systems based on piezoelectric materials. The structures of piezoelectric sensors in the measurement systems are discussed. Hardware design applied to measurement system is summarized. Moreover, the main point of further study is presented in this paper.

There are two commercially accepted methods of force control used in automated surface finishing today. The first method, “through‐the‐arm” force control, applies force using the position of all the robot axes in unison. The second method, “around‐the‐arm” force control, uses the robot for positioning motion only, and applies a controlled force through an auxiliary‐compliant end‐of‐arm tool. Discusses the theory, applicability and features of each of these two technologies.

This paper aims to present an effective sensing detection system based on fiber Bragg grating (FBG) sensing technology for protective barriers that have been effectively applied to intercept and stop rocks from falling onto railway tracks. . Determination of exact stress and deformation values during impact tests for key components of the protective barrier forms important criteria for quality control of these barriers. Monitoring changes in force along the protective barrier when deployed in field application allows for real-time disaster warning for collapse and falling rocks.

In this paper, we propose a monitoring strategy for key components of a protective barrier. During performance tests, dynamic force and strain were measured for the steel strands and supporting I-beam, respectively. Design of a special elastic structure for the force transducer based on finite element analysis and tensile tests has been discussed here. Two types of FBG force transducers were manufactured based on the elastic structure. Four FBG force transducers and four FBG strain sensors were used for impact verification testing of a new rigid protective barrier with a design protection level of 25 KJ.

Dynamic force and strain responses were obtained during an impact of free-falling block with a kinetic energy of 25 KJ.

The FBG monitoring scheme can be extremely valuable for optimized design of the barrier and can provide real-time disaster warning in regions of collapse and falling rocks.

Wheel force transducers (WFTs) have performance characteristics that make them attractive for applications in endurance evaluation of road vehicles, ride and handling optimization, tire development and vehicle dynamics. As a WFT is mounted on the the driven wheel, the loads on the wheel and the outputs of WFTs are usually nonlinearly related. Thus, a real-time filter is needed to measure the true loads on the wheel.

In this paper, a new nonlinear filtering algorithm utilizing quadrature Kalman filter (QKF) is proposed to track the actual loads in real time through establishing the specific observation equations with Singer models.

The simulation results show that the accuracy and the rapidity of QKF outperforms the capability of the unscented Kalman filter (UKF). Then, the dynamic tests on the MTS testing platform give the comparisons between the real-time QKF and the wavelet transform, where the former has superior dynamic accuracy. Finally, the practical tests of shifting and braking on a real vehicle confirm the effectiveness of QKF, which further validates the proposed method fitting reality.

In this paper, a newly improved algorithm with QKF for WFT has been proposed and tested experimentally. As the wheel loads are always time-varying and complex, introducing Gaussian noise in the outputs of the transducer, WFT-suitable Singer model and WFT measurement equation base on a QKF are established. The experiment results show that QKF has advanced performance than the traditional UKF. Also, the road wheel test bed produced by MTS has been exploited as the test platform to demonstrate the dynamic efficiency of the proposed real-time filter under various operating conditions for a wide range of loads. And, the practical tests with the real vehicle are accomplished to verify the value and effectiveness of the proposed method.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.