A novel one-dimensional force sensor calibration method to improve the contact force solution accuracy for legged robot

As a mechanical component, sensor can detect spatial information. Sensor technology has been widely used in national defense, aerospace, industrial inspection and automated production areas and so on. However, the sensor calibration device cannot meet the demand of the development of the sensor. In this paper, a multi-functional force loading device, which is of good technical performance, reliable operation, wide measurement range and simple measurement method, and a six-dimensional force sensor calibration method are described.

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Hexapod Adaptive Gait Inspired by Human Behavior for Six-Legged Robot Without Force Sensor

Journal of Intelligent & Robotic Systems ◽

10.1007/s10846-017-0532-7 ◽

2017 ◽

Vol 88 (1) ◽

pp. 19-35 ◽

Cited By ~ 6

Author(s):

Yilin Xu ◽

Feng Gao ◽

Yang Pan ◽

Xun Chai

Keyword(s):

Human Behavior ◽

Force Sensor ◽

Legged Robot ◽

Adaptive Gait

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A stance period approach for simplified observation of galloping as applied to canines

Robotica ◽

10.1017/s0263574711000488 ◽

2011 ◽

Vol 30 (4) ◽

pp. 627-633

Author(s):

Surya P. N. Singh ◽

Kenneth J. Waldron

Keyword(s):

Parameter Estimation ◽

Conceptual Framework ◽

Motion Capture ◽

Contact Force ◽

Inverse Dynamics ◽

Force Plate ◽

Setup Times ◽

Legged Robot ◽

Impulse Model ◽

Leg Motion

SUMMARYThe gallop is the preferred gait by mammals for agile traversal through terrain. This motion is intrinsically complex as the feet are used individually and asymmetrically. Simple models provide a conceptual framework for understanding this gait. In this light, this paper considers the footfall projections as suggested by an impulse model for galloping as a measurement simplifying strategy. Instead of concentrating on forces and inverse dynamics, this view focuses observations on leg motion (footfalls and stance periods) for subsequent gallop analysis and parameter estimation. In practice, this eases experiments (particularly for IR-based motion capture) by extending the experimental workspace, removing the need for single-leg contact force-plate measurements, and reducing the marker set. This provides shorter setup times, and it reduces postprocessing as data are less likely to suffer from occlusion, errant correspondence, and tissue flexion. This approach is tested using with three canine subjects (ranging from 8 to 24 kg) performing primarily rotary gallops down a 15 m runway. Normalized results are in keeping with insights from previous animal and legged robot studies and are consistent with motions suggested by said impulse model.

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Research on PVDF Micro-Force Sensor

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.599-601.1135 ◽

2014 ◽

Vol 599-601 ◽

pp. 1135-1138

Author(s):

Chao Zhe Ma ◽

Jin Song Du ◽

Yi Yang Liu

Keyword(s):

Power Dissipation ◽

Polyvinylidene Fluoride ◽

High Sensitivity ◽

Force Sensor ◽

Calibration Method ◽

Pvdf Film ◽

Force Sensors ◽

Low Power Dissipation ◽

Micro Force Sensor ◽

Processing Circuit

At present, sub-micro-Newton (sub-μN) micro-force in micro-assembly and micro-manipulation is not able to be measured reliably. The piezoelectric micro-force sensors offer a lot of advantages for MEMS applications such as low power dissipation, high sensitivity, and easily integrated with piezoelectric micro-actuators. In spite of many advantages above, the research efforts are relatively limited compared to piezoresistive micro-force sensors. In this paper, Sensitive component is polyvinylidene fluoride (PVDF) and the research object is micro-force sensor based on PVDF film. Moreover, the model of micro-force and sensor’s output voltage is built up, signal processing circuit is designed, and a novel calibration method of micro-force sensor is designed to reliably measure force in the range of sub-μN. The experimental results show the PVDF sensor is designed in this paper with sub-μN resolution.

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Vision Sensor Calibration Method based on Flexible 3d Target and Invariance of Cross Ratio

Proceedings of the First International Conference on Information Sciences, Machinery, Materials and Energy ◽

10.2991/icismme-15.2015.313 ◽

2015 ◽

Cited By ~ 2

Author(s):

Jingli Wei ◽

Zhiwei Liu ◽

Fangling Cheng

Keyword(s):

Calibration Method ◽

Cross Ratio ◽

Sensor Calibration ◽

Vision Sensor

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A novel testing system for biomechanical evaluation of the bone or bone fixator

Sensor Review ◽

10.1108/sr-11-2017-0234 ◽

2018 ◽

Vol 38 (4) ◽

pp. 405-411

Author(s):

Zhanshe Guo ◽

Zhaojun Guo ◽

Xiangdang Liang ◽

Shen Liu

Keyword(s):

Good Condition ◽

Force Sensor ◽

Biomechanical Properties ◽

Biomechanical Study ◽

Sensor Calibration ◽

Testing System ◽

Static Force ◽

Content Type ◽

New Device ◽

Bending Force

Purpose Biomechanical properties of bones and fixators are important. The aim of this study was to develop a new device to simulate the real mechanical environment and to evaluate biomechanical properties of the bone with a fixation device, including the static force and the fatigue characters. Design/methodology/approach In this paper, the device is mainly composed of three parts: pull-pressure transmission system, bending force applying system and torsion applying system, which can successfully simulate the pre-introduced pull-pressure force, bending force and torsion force, respectively. To prove the feasibility of the design, theoretical analysis is used. It is concluded from the simulated result that this scheme of design can successfully satisfy the request of the evaluation. Findings Finally, on the basis of the force sensor calibration, the static force experiment and fatigue experiment are carried out using the tibia of the sheep as the specimen. It is concluded from the result that the relationship between the micro displacement and the applied axial force is nearly linear. Under the condition of 1 Hz in frequency, 500 N in loading force and 18,000 reciprocating cycles, the bone fixator can still be in good condition, which proves the feasibility of the design. Originality/value Biomechanical properties of bones and fixators are studied by researchers. However, few simulate a real force environment and combine forces in different directions. So a novel system is designed and fabricated to evaluate the biomechanical properties of the bones and fixators. Results of the experiments show that this new system is reliable and stable, which can support the biomechanical study and clinical treatment.

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A Novel Camera One-Dimensional Calibration Method

Acta Optica Sinica ◽

10.3788/aos201636.1215005 ◽

2016 ◽

Vol 36 (12) ◽

pp. 1215005

Author(s):

吕耀文 Lü Yaowen ◽

刘维 Liu Wei ◽

徐熙平 Xu Xiping ◽

安喆 An Zhe

Keyword(s):

Calibration Method ◽

One Dimensional

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A Normal Sensor Calibration Method Based on an Extended Kalman Filter for Robotic Drilling

Sensors ◽

10.3390/s18103485 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3485 ◽

Cited By ~ 4

Author(s):

Dongdong Chen ◽

Peijiang Yuan ◽

Tianmiao Wang ◽

Ying Cai ◽

Haiyang Tang

Keyword(s):

Kalman Filter ◽

Laser Beam ◽

Extended Kalman Filter ◽

Zero Point ◽

Calibration Method ◽

Sensor Calibration ◽

Beam Direction ◽

Displacement Sensors ◽

Robotic Drilling ◽

Drilling System

To enhance the perpendicularity accuracy in the robotic drilling system, a normal sensor calibration method is proposed to identify the errors of the zero point and laser beam direction of laser displacement sensors simultaneously. The procedure of normal adjustment of the robotic drilling system is introduced firstly. Next the measurement model of the zero point and laser beam direction on a datum plane is constructed based on the principle of the distance measurement for laser displacement sensors. An extended Kalman filter algorithm is used to identify the sensor errors. Then the surface normal measurement and attitude adjustments are presented to ensure that the axis of the drill bit coincides with the normal at drilling point. Finally, simulations are conducted to study the performance of the proposed calibration method and experiments are carried out on a robotic drilling system. The simulation and experimental results show that the perpendicularity of the hole is within 0.2°. They also demonstrate that the proposed calibration method has high accuracy of parameter identification and lays a basis for high-precision perpendicularity accuracy of drilling in the robotic drilling system.

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Development and Application of a Tandem Force Sensor

Sensors ◽

10.3390/s20216042 ◽

2020 ◽

Vol 20 (21) ◽

pp. 6042

Author(s):

Zhijian Zhang ◽

Youping Chen ◽

Dailin Zhang

Keyword(s):

Contact Force ◽

Mechanical Model ◽

Traction Force ◽

Force Sensor ◽

Teaching Experiment ◽

Contact Forces ◽

Contact Tasks

In robot teaching for contact tasks, it is necessary to not only accurately perceive the traction force exerted by hands, but also to perceive the contact force at the robot end. This paper develops a tandem force sensor to detect traction and contact forces. As a component of the tandem force sensor, a cylindrical traction force sensor is developed to detect the traction force applied by hands. Its structure is designed to be suitable for humans to operate, and the mechanical model of its cylinder-shaped elastic structural body has been analyzed. After calibration, the cylindrical traction force sensor is proven to be able to detect forces/moments with small errors. Then, a tandem force sensor is developed based on the developed cylindrical traction force sensor and a wrist force sensor. The robot teaching experiment of drawer switches were made and the results confirm that the developed traction force sensor is simple to operate and the tandem force sensor can achieve the perception of the traction and contact forces.

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Development of a Novel Micro-Gripper Integrating Tri-Axial Force Sensor

First International Conference on Integration and Commercialization of Micro and Nanosystems, Parts A and B ◽

10.1115/mnc2007-21035 ◽

2007 ◽

Author(s):

Jiachou Wang ◽

Weibin Rong ◽

Lining Sun ◽

Hui Xie ◽

Wei Chen

Keyword(s):

Axial Force ◽

Crystalline Silicon ◽

Force Sensor ◽

Calibration Method ◽

Deep Reactive Ion Etching ◽

Micro Gripper ◽

The Cross ◽

Silicon Frame ◽

High Level ◽

Cross Structure

A novel micro gripper integrating tri-axial force sensor and two grades displacement amplifier is presented in this paper, which bases on the technology of Piezoresistive detection and use PZT as its micro driving component. The micro tri-axial force sensor is fabricated on a single-crystalline-silicon by the technology of MEMS and consists of a flexible cross-structure realized by deep reactive ion etching (DRIE). The arms of the cross-structure are connected to a silicon frame and to the central part of the cross-structure. After modeling the amplifier structure of micro gripper and the sensor, finite element method (FEM) is used to analyze the displacement of the micro gripper and the deformation of the cross-structure elastic cantilever. A calibration method of tri-axial sensor based on the technology of microscopic vision and the principle of bending deflection cantilever is proposed. The experimental verified that the sensor are high level of intrinsic decoupling of the signals from strain gauge, high resolutions in all three axes, high linearity and repeatability and simple produce of calculation. And also show the micro gripper is reasonable and practical. The sensor is capable of resolving forces up to 10mN with resolution of 2.4μN in x axis and y axis and up to 10mN with resolution of 4.2μN in z axis; the gripping displacement of the micro gripper is from 20μm to 300μm.

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