INTRODUCTION TO COMPLIANT MECHANISM
General compliant mechanism
A mechanism is a system of mechanical components designed to convert input loads and movements into specific outputs It consists of interconnected rigid links and ideal rigid joints, referred to as kinematic pairs, which facilitate relative movement between the links These joints effectively constrain the motion between the links, minimizing any undesired movements resulting from deformations and elasticity.
Compliant mechanisms utilize flexibility and elasticity to generate desired relative motions, achieving mobility by transforming input force or energy into output motion through elastic deformation This process is made possible by the incorporation of flexible components within the mechanism.
The use of compliant members dates back to the late Paleolithic period, around 35,000 to 8000 BC, coinciding with the invention of archery for hunting and warfare The bowstring's pull stored strain energy, which converted into the kinetic energy of the arrow upon release This principle was subsequently adapted for heavier weaponry, including the catapults employed by the Syracusean Greeks in 399 BC.
BC Catapults were used as artillery in early battles to launch heavy objects or arrows over large distances
The Greek Palintone catapult exemplifies the early use of compliant mechanisms, utilizing tightly coiled rope as a torsional spring for strain energy While these mechanisms were primarily confined to war machines in the past, their significance has expanded dramatically in recent years Today, compliant mechanisms are essential in diverse fields such as micro-electromechanical systems, robotics, precision engineering, and biomechanics, and they are commonly found in everyday applications.
Figure 1 1 The bow and arrow [12] Figure 1 2 Greek palintone [12]
Mechanisms are mechanical devices designed to transfer motion, force, or energy within a mechanical system Typically composed of rigid links connected by joints, these mechanisms facilitate specific movements or energy transfers For instance, a linear input can be converted into rotational output, and input force can be transformed into output torque A practical example is vice grips, which effectively transfer energy from the user's hand to the gripper teeth.
These essences are of particular interest to researchers and engineers who are engaged in micro-and nano-positioning development [3 - 5], lithography engineering [6, 7], and MEMS process [ 8- 10], where high precision is required
Figure 1 3 (a) part of reciprocating engine (b)Vise Grip [1]
Figure 1 4 Commonly used compliant devices: Binder clips, paper clips, hair clips, backpack latch, eyelash curlers and nail clippers [12]
Compliant mechanisms can greatly reduce the number of components required compared to traditional rigid-body mechanisms by employing flexible elements instead of conventional rigid parts like springs, pins, and hinges.
Compliant mechanisms are known for their manufacturing simplicity, as they can be produced using various techniques Their design, which incorporates flexible elements for movement, enables many to be created from flat, planar sheets of material Common manufacturing methods for compliant mechanisms include machining, stamping, laser cutting, water-jet cutting, 3D printing, and electrical discharge machining.
Compliant mechanisms offer significant cost-effectiveness due to their simple design and manufacturing processes, which reduce the number of necessary parts This simplification not only streamlines production but also lowers both manufacturing and assembly times, ultimately decreasing costs Their flexible design allows for various manufacturing methods, enhancing their affordability across different applications.
Compliant mechanisms enhance precision in motion by minimizing issues like backlash and wear commonly found in traditional mechanisms By utilizing bending materials instead of rigid pins and hinges, these mechanisms significantly reduce wear, leading to improved movement accuracy This approach is particularly beneficial in instrumentation design, as it also helps decrease vibration and noise in various applications.
Compliant mechanisms enhance performance by minimizing movable joints, which leads to reduced friction and eliminates the need for lubrication This advantage is especially beneficial in hard-to-reach applications or harsh environments that can adversely affect traditional joints In particular, space applications highlight this relevance, as lubricants can evaporate under low-gravity conditions.
● Scalability: Compliant mechanisms can be easily miniaturized, making them ideal for the development of microstructures, actuators, sensors, and other
5 microelectromechanical systems (MEMS) The fewer parts and joints in compliant mechanisms are a key factor in the production of small-scale mechanisms
Compliant mechanisms offer a lightweight design that can greatly decrease weight compared to traditional rigid-body mechanisms, making them ideal for industries like aerospace and for products requiring shipping This reduction in weight not only enhances performance but also helps companies save on shipping costs for consumer products.
Compliant mechanisms leverage flexible components to store energy as strain energy, akin to the properties of springs This design allows for the storage and transformation of energy for later use, exemplified by a bow and arrow system where energy is accumulated in the bow's limbs and converted into the arrow's kinetic energy Such energy storage capabilities enable the design of mechanisms with tailored force-deflection properties or facilitate movement toward a specified position.
● Despite their advantages, compliant mechanisms also have some challenges when used in specific applications
● Restricted Movement: Compliant mechanisms rely on material deformation to generate movement between rigid parts, leading to a limited range of motion and the inability to perform continuous movements
Unwanted movements in compliant mechanisms often lead to secondary, unintended motions known as parasitic motions These parasitic motions arise from the complex deformation behavior inherent in these systems, impacting their overall performance and precision.
Compliant mechanisms present significant challenges in analysis and design, requiring a deep understanding of mechanism analysis, synthesis methods, and the behavior of flexible element deflections The presence of geometric nonlinearities due to large deflections renders traditional linear beam equations ineffective for these flexible components.
Compliant mechanisms often experience significant deflections, leading to their design primarily through trial and error methods This approach is effective only for simple systems that perform basic tasks with minimal displacements To accurately model these mechanisms, a pseudo-rigid-body model is utilized, depicting the compliant components as multiple rigid bodies linked by a pin joint.
Purpose, mission and limitation
Compliant mechanisms are designed to deform elastically under applied forces and return to their original shape once the force is removed Specifically, XY-compliant mechanisms enable movement along both the X and Y axes, making them suitable for applications in microelectronics, micromachines, and precision positioning systems These mechanisms provide several advantages over traditional rigid designs, including enhanced precision, reduced costs, and improved adaptability to environmental changes.
XY Compliant Mechanisms are designed for precise positioning and motion tasks, offering high accuracy along with flexibility to absorb external forces Their applications span micro- and nanoscale robotics, medical devices, and scientific instrumentation The specific mission of each mechanism varies based on the unique requirements of its intended application.
1 Complexity: XY-compliant mechanisms are complex in nature and require intricate designs to achieve the desired level of precision and accuracy
2 Sensitivity: XY-compliant mechanisms are often highly sensitive to changes in temperature and humidity, which can result in significant variations in their performance over time
3 Cost: Due to their complex design and the specialized materials used, XY-compliant mechanisms are often expensive to produce and maintain
4 Precision: The precision of XY-compliant mechanisms is often limited by the accuracy of the manufacturing processes used to produce them
5 Durability: XY-compliant mechanisms are often subject to wear and tear over time, which can result in the degradation of their performance and functionality
6 Complex Assembly: XY-compliant mechanisms often require complex assembly procedures and a high level of expertise to install and maintain
DOMESTIC AND INTERNATIONAL RESEARCH
International research
To date, there are researches in China, Hong Kong:
A novel compliant XY micro-positioning stage using bridge-type displacement amplifier embedded with Scott-Russell mechanism - Haitao Wu, Leijie Lai, Limin Zhu
A large range compliant XY nano-manipulator with active parasitic rotation rejection
Design, modeling, and analysis of a completely-decoupled XY compliant parallel manipulator - Guangbo Hao, Jingjun Yu (2016)
On a simplified nonlinear analytical model for the characterization and design optimization of a compliant XY micro-motion stage - Xavier Herpe, Ross Walker, Xianwen Kong (2018)
Design of compliant mechanisms based on compliant building elements - Chenglin
Investigations of a compliant manipulator implementing micro-scale 2D displacements - S Chwastek, A Gawlik, G Tora (2022)
A constraint-flow-based method of synthesizing XYθ compliant parallel mechanisms with decoupled motion and actuation characteristics - Haiyang Li, Yijie Liu, Guangbo Hao
Domestic research
In Vietnam, there is a notable lack of research in the field of "Design and Optimization of Soft Mechanisms for Precision Grippers," as highlighted by Dr Dao Thanh Phong in 2021.
My colleagues and I have launched a study focused on the application of soft mechanisms in locators, addressing the lack of domestic research in this area We aim to contribute valuable insights that will encourage further exploration of this topic in Vietnam.
18 more research, processing, and design on 2-DOF XY positioners, to advance the development of nanotechnology in industries such as semiconductors, medicine, electronics, and precise positioning.
Research direction
A thorough literature review on compliant mechanisms is essential to grasp the current landscape of the field, pinpoint existing knowledge gaps, and highlight potential areas for future research.
Performance analysis: Analyze the performance of existing compliant mechanisms and compare them to traditional mechanisms to determine their advantages and limitations
Design optimization: Conduct optimization studies to determine the optimal design parameters and trade-offs for compliant mechanisms in different applications
Simulation and modeling: Develop and validate simulation models to predict the behavior of compliant mechanisms and compare them to experimental data
Fabrication and testing: Fabricate and test prototypes of compliant mechanisms to validate simulation results and refine the design
Application analysis: Analyze the potential applications of compliant mechanisms in different fields, such as biomedical engineering, aerospace engineering, and consumer products, to determine their suitability and potential impact
Market analysis: Conduct market analysis to determine the potential demand for compliant mechanisms and identify potential customers and partners
1 Incorporate new materials: Consider using advanced materials such as flexible polymers or shape memory alloys to enhance the compliance and performance of the mechanism
2 Utilize advanced manufacturing techniques: Utilize advanced manufacturing techniques such as 3D printing or microfabrication to enhance the precision and accuracy of the mechanism
3 Integrate sensors and actuators: Incorporate sensors and actuators into the mechanism to improve its control and feedback capabilities
4 Conduct simulations and modeling: Use computer simulations and modeling to optimize the design and performance of the mechanism before building a physical prototype
5 Collaborate with industry partners: Collaborate with industry partners to gain insight into real-world applications and requirements for the mechanism, and to validate its performance in actual use
6 Incorporate artificial intelligence and machine learning: Utilize artificial intelligence and machine learning algorithms to enhance the control and feedback capabilities of the mechanism, and to improve its overall performance
7 Consider incorporating smart materials: Consider incorporating smart materials, such as piezoelectric materials or materials that exhibit changes in response to external stimuli, to enhance the functionality of the mechanism
These suggestions can help to improve the design, performance, and compliance of an XY-compliant mechanism and can lead to more advanced solutions in various industries
The development of mechanisms that are compliant with the XY standard or requirement is becoming increasingly important for ensuring improved performance and safety in a range of industries
Problem Statement: Despite the widespread use of mechanisms in various industries, there is a lack of solutions that fully comply with the XY standard or requirement This has
Concerns regarding performance and safety have hindered the widespread adoption of certain mechanisms This research aims to create a mechanism that adheres to the XY standard while offering enhanced performance and safety over current solutions.
The primary objectives of this research are to:
● Develop a mechanism that fully complies with the XY standard or requirement
● Evaluate the performance and safety of the mechanism against existing solutions
● Demonstrate improved performance and safety compared to existing solutions
● Methodology: The methodology will involve the following steps:
Design and development of a mechanism that complies with the XY standard or requirement
Testing and validation of the mechanism to ensure it meets the required specifications and requirements
Comparison of the performance and safety of the mechanism against existing solutions
Refinement of the mechanism based on the results of the testing and validation
Timeline: The research is expected to take approximately 12 months to complete, with the following key milestones:
● Month 1-3: Literature review and initial design of the mechanism
● Month 4-6: Development and testing of the mechanism
● Month 7-9: Refinement and validation of the mechanism
● Month 10-12: Final testing, reporting, and dissemination of results.
Reachable workspace
The reachable workspace of a compliant mechanism defines the maximum area where the mechanism can be effectively positioned and manipulated Typically, compliant mechanisms offer a more limited reachable workspace than traditional rigid mechanisms.
21 due to their inherent flexibility However, they also have unique advantages in terms of precision, efficiency, and adaptability
The reachable workspace of compliant mechanisms is crucial in micro-scale applications like micro-manipulation, micro-assembly, and microrobotics These mechanisms must effectively accommodate small components while ensuring the required dexterity and accuracy for precise interactions.
To optimize compliant mechanisms with a reachable workspace of approximately 1mm, it is essential to balance flexibility and stability Utilizing materials with a high modulus and low yield strength, such as high-strength steels and alloys, can minimize deformation and enhance stability Furthermore, employing precise fabrication techniques like micro-machining and micro-fabrication ensures accurate and consistent performance.
The configuration and geometry of a compliant mechanism significantly impact its reachable workspace Incorporating articulated joints like hinges and sliders enhances degrees of freedom, thereby expanding the workspace Additionally, utilizing multiple segments such as links and actuators allows the mechanism to access various regions and orientations, further increasing its reachable workspace.
In summary, the reachable workspace of a compliant mechanism is essential for its design and performance For mechanisms with a workspace of approximately 1mm, it is crucial to thoughtfully select materials, fabrication techniques, configurations, and geometries to optimize functionality By integrating advanced design and fabrication methods with innovative materials and components, high-precision and high-performance compliant mechanisms can be developed, achieving a reachable workspace around 1mm.
The area workspace can reach to 7 mm because of the Equivalent stress must under
KINEMATIC XY MECHANISM DSIGN
Design and calculate 2-DOF compliant stage
The two-degree-of-freedom (DOF) positioning platform can be configured using either serial or parallel mechanisms Although the serial mechanism features a simple design, it has significant drawbacks, such as the accumulation of positioning errors over time, which diminishes the platform's motion accuracy Additionally, the increased mass of moving parts in a serial configuration leads to a reduction in the platform's response speed.
Parallel mechanisms provide significant benefits such as enhanced rigidity, accuracy, load capacity, and consistent performance across multiple axes, leading to increased interest in their application However, their design and modeling present challenges, particularly regarding output cross-axis decoupling, which ensures that each actuator exclusively drives the central stage in one axial direction without interference This is especially critical for piezoelectric actuators (PEAs), which are vulnerable to lateral forces and bending, as any coupling can result in damage Traditional mechanisms typically exhibit a coupling ratio ranging from 1% to 1.5% (Li et al., 2012; Xu).
2014), so it is important to develop a decoupled design for parallel mechanisms in order to reduce coupling and improve performance
In summary, parallel mechanisms are often favored over serial mechanisms due to their superior rigidity, accuracy, and reliable performance Nevertheless, the design of parallel mechanisms is more intricate, as it requires the decoupling of the outputs from the two axes.
The proposed design for the 2-DOF stage features a parallelogram mechanism combined with a multi-lever amplifier To develop the stage's dynamic equation, analytical modeling is utilized alongside the response surface method (RSM) The optimization algorithm for this stage is visually represented in Figure 2.1, which outlines the key steps involved in the process.
● Theoretical modeling and analysis to understand the kinematic and dynamic behavior of the mechanism
Numerical simulation through software like Finite Element Analysis (FEA) is essential for validating theoretical models and examining how various design parameters influence the performance of mechanisms.
● Experimental testing of prototypes to validate the numerical simulations and to measure the performance of the mechanism under real-world conditions
● Optimization studies to determine the optimal design parameters that result in the best performance of the mechanism
The research method employed varies based on the project's specific goals and requirements, often utilizing a combination of approaches to gain a thorough understanding of the behavior of XY compliant mechanisms.
Kinetostatic and dynamic modeling analysis
The study employed the Response Surface Method (RSM) for design testing and analysis, utilizing Inventor Professional 2015 to create the platform model, which was then imported into ANSYS 19.2 for finite element analysis This approach enabled the prediction of output displacement, maximum equivalent stress, and maximum safety factor with high precision The analysis was enhanced by applying an automatic meshing method in coarse areas of the model while refining the flexure hinge for improved accuracy.
The analysis established boundary conditions to accurately reflect real-world scenarios, fixing the platform at the holes and applying specific conditions Utilizing Response Surface Methodology (RSM) enabled predictions regarding the platform's performance and behavior, highlighting potential weaknesses for enhancement The insights gained facilitated design refinements, ensuring the platform adhered to essential safety standards and operated optimally under diverse conditions RSM played a vital role in guaranteeing the platform's safety and reliability.
The linear analytical model has limitations in accurately representing variations in stiffness due to changes in loads and displacements, making it applicable only within a very restricted range.
To comprehend the characteristics of the proposed XY, a combination of free body diagram (FBD) modeling and beam constraint modeling (BCM) was utilized The BCM approach effectively addresses nonlinearities and delivers a closed-form model capable of accurately predicting the kinetostatic behavior of a generalized beam subjected to different loads, such as transverse force, axial force, and moment.
Figure 3 1 The geometry parameter and loading condition of the DPF[11]
Figure 3 2 Pseudo-rigid body diagram for 2-DOF stage
3.2.1 The Response Surfaces Method (RSM) a) Theory
The Response Surface Method (RSM) is a statistical optimization technique that explores the relationship between multiple response variables and various input variables It is especially beneficial for complex systems where the connections between inputs and outputs are unclear or challenging to predict using conventional methods.
In compliant mechanism design, Response Surface Methodology (RSM) is utilized to evaluate how design parameters influence performance metrics Specifically, RSM helps assess the effects of material properties, dimensions, and geometries on key factors such as displacement, amplification ratio, and safety factor of compliant mechanisms.
Response Surface Methodology (RSM) utilizes mathematical modeling to forecast the output of compliant mechanisms based on various design parameter combinations This approach aids in pinpointing the design parameters that yield optimal performance, making RSM an essential tool for efficiently navigating extensive design spaces and identifying optimal designs that fulfill specific performance criteria.
RSM offers essential insights into how design parameters influence performance metrics, enabling engineers to comprehend the impact of their design decisions on compliant mechanisms This knowledge serves as a valuable guide in the design process, ultimately enhancing the performance of these mechanisms.
There are several types of response surface methods (RSMs), including:
1 Central composite design (CCD): This type of RSM involves a combination of factorial and axial points to fit a second-degree polynomial model to the response surface The design is efficient for fitting second-degree polynomial models and is suitable for problems with a small number of design variables
2 Box-Behnken design: This type of RSM is similar to CCD but uses a different arrangement of design points The design is efficient for fitting second-degree polynomial models and is suitable for problems with a small number of design variables
3 Factorial design: This type of RSM involves using a factorial design to fit a polynomial model to the response surface Factorial designs are simple and easy to generate, but may not be efficient for fitting more complex models
4 Response surface regression (RSR): This type of RSM uses multiple regression techniques to fit a polynomial model to the response surface RSR is suitable for problems with a large number of design variables, but may be computationally intensive
5 Mixture design: This type of RSM involves using a design that combines factorial and axial points to fit a polynomial model to the response surface Mixture designs are efficient for fitting models with a small number of design variables
6 Kriging: This type of RSM uses a stochastic model to fit the response surface Kriging is a flexible method that can handle a wide range of models, but may be computationally intensive
In summary, various response surface methods (RSM) exist, each offering unique benefits and drawbacks Selecting the appropriate RSM is contingent upon the specific problem at hand and the required level of computational effort.
Design of Experiment (DOE) is a statistical approach that systematically varies input factors to analyze their relationship with output responses Its primary objective is to determine the optimal combination of these factors for achieving desired results while modeling their interactions DOE finds applications across diverse fields such as engineering, science, and medicine, facilitating the optimization of product design, enhancement of processes, and innovation in new products and technologies.
The following steps are involved in a typical DOE process:
1 Define the problem: Identify the inputs and outputs that need to be studied and define the goals and objectives of the experiment
2 Choose an experimental design: Choose a suitable experimental design that meets the goals and objectives of the experiment, such as full factorial, fractional factorial, response surface, or custom designs
3 Run the experiments: Vary the input factors according to the experimental design and measure the corresponding output responses
4 Analyze the data: Use statistical methods to analyze the data and fit a mathematical model to the relationship between input factors and output responses
5 Optimize the design: Use the model to identify the optimal combination of input factors that result in the desired output responses
6 Validate the model: Validate the model by comparing its predictions with the results from additional experiments or simulations
7 Apply the results: Use the optimized design or the model to improve products, processes, or technologies
Inspired from the Symbol of swastika 卐, so we have designed XY compliant with a mirror-symmetrical and 6 half-bridge level amplifiers.
Figure 2 6 Proposed compliant 2-DOF stage
Figure 2 8 Dimensional schematic of proposed stage
Symbol Value Unit Symbol Value Unit a 360 mm o 6 mm b 490 mm p 40 mm c 128 mm q 5,6 mm
34 d 85,4 mm r R4 mm e 24 mm s 6 mm f 85,4 mm t 45,6 mm g 24 mm u 60 mm h 10,7 mm v 0,8 mm i 15 mm w 30 mm j 113 mm x 8,6 mm k 24 mm y 55,5 mm l 140 mm S1 0.7⩽ S1 ⩽0.9 mm m 16 mm S2 0.6⩽ S2 ⩽0.7 mm n 10 mm S3 0.5⩽ S3 ⩽0.6 mm
Define input conditions: Right click Static Structural -> Insert -> Fixed support After that choose faces which need to be fixed.
VERIFICATION AND EVALUATION WITH FEA
Model verification
We utilized ANSYS R19.2 to simulate and derive the design variables for the optimal candidate, which were then used to reconstruct the finite element analysis (FEA) model in ANSYS This process was executed using the same response surface and input displacement, with the FEA model results aligning with the predictions from the response surface analysis.
Discussions
The analysis reveals a y-axis displacement of 55 àm and an x-axis displacement of -55 àm, highlighting the extent of deformation in the system These deformation values are essential for evaluating the system's overall performance and efficiency.
The maximum deformation measured along the y-axis reached -641.6 àm, while the x-axis recorded a maximum deformation of 649.12 àm These measurements highlight the system's capacity to withstand deformation, offering valuable insights into its overall strength and resilience.
The calculated maximum equivalent stress was 275.11 MPa, with a minimum safety factor of 1.8284 These metrics indicate the stress levels the system endures and its capacity to withstand such stress The equivalent stress is essential as it reflects the force acting on the system, while the safety factor signifies the available safety margin for unexpected stress increases.
In summary, understanding the displacement, maximum probed deformation, maximum equivalent stress, and minimum safety factor is essential for assessing the system's performance and reliability These metrics highlight areas for improvement and serve as a foundation for future advancements.
OPTIMIZATION
Optimization problem
1 Balancing compliance and rigidity: The mechanism must be compliant enough to conform to the XY standard or requirement, while also maintaining the required rigidity and stability to perform its intended function
2 Minimizing weight and size: The mechanism must be as lightweight and compact as possible to enhance its performance, while also satisfying the requirements of the XY standard
3 Maximizing efficiency: The mechanism must be as efficient as possible in terms of power consumption, heat dissipation, and other performance criteria
4 Minimizing cost: The mechanism must be cost-effective to produce, and to integrate into the overall system, while also satisfying the requirements of the XY standard
Addressing optimization challenges necessitates balancing conflicting design goals while accounting for constraints like available materials, manufacturing processes, and performance standards This process demands a multidisciplinary approach that combines insights from mechanics, materials science, control engineering, and other pertinent disciplines.
Optimal result
Figure 5 1 Fixed support and input displacement
Table 3 Bound of the response surface
Deformation Probe Maximum Y Axis Maximize μm
Deformation Probe Maximum X Axis Maximize
In our research-focused project, we established boundary values and conducted multiple evaluations as guided by our instructor For the assessment of all candidate values, our team ultimately selected candidate 3 for its optimal suitability.
Table 5 Selected parameter after optimization
Simulation result
There are some charts in simulation
EXPERIMENTAL TESTS
Manufacturing
The compliant mechanism was fabricated using the wire cutting method, which offers significant advantages, including cost efficiency The material chosen for this process was 7075 aluminum, known for its high yield strength-to-Young's modulus ratio, allowing it to endure greater deflection before failure This method was particularly beneficial for creating the single degree of freedom stage sample.
The 2-DOF Amplifier can be manufactured using Wire cutting method and CNC machining The overlapping relation relationship between the plate and the base are secured by bolted joins or adhesive bonding
Introduce about Wire cutting method
The wire cutting technique is a precise manufacturing process that utilizes a thin wire tool, produced through electrical discharge machining (EDM), to create intricate shapes from metal and other materials This method effectively erodes material through spark erosion, making it especially valuable for cutting hard-to-process materials, and is commonly employed in the production of molds and dies.
Wire cutting provides numerous benefits, including exceptional precision and non-contact processing that minimizes tool wear and protects the workpiece from damage It is versatile, compatible with various materials, and excels in machining hard substances Additionally, wire cutting allows for the creation of intricate shapes while preventing thermal damage to the material.
Experimental set up
The 2 Degree-of-Freedom stage is illustrated in Figure 6.3, while the complete experimental setup is shown in Figure 6.4, featuring the compliant mechanism, base, and piezo microphone actuators Following the manufacturing and assembly of components, open loop experiments are conducted under a microscope to analyze the mechanism's behavior during actuator operation The piezo microphone actuators can be controlled manually by turning the actuator shafts or automatically through voltage signals The displacement of the triangular stage is monitored using cameras, with a small dot placed on the stage for tracking, as depicted in Figure 6.4 The pixel coordinates of this point are extracted from the camera images and converted into world coordinates for precise measurement.
55 Figure 6 3 Displacement device set-up
Figure 6 4 Actual measuring set-up by Digital indicator
Open test
Measuring displacement by laser sensor:
Figure 6 5 Experimental set-up workspace test by laser sensor
Laser base sensor Optical table
Measuring times Input displacement Output displacement Unit
The study conducted in the ANSYS environment yielded a simulated data value of 641 àm, which was optimized to 628 àm with a 2% error rate However, discrepancies between experimental and simulated data can arise due to external factors such as temperature variations, inaccuracies in measuring equipment, and machining errors during manufacturing Environmental influences like vibration may also lead to data deviations Thus, it is vital to consider these external factors when analyzing experimental results to ensure reliability and attribute variations to tested variables rather than external influences In conclusion, while ANSYS is an effective tool for data simulation, recognizing the impact of external factors is essential for accurate experimental interpretation.
CONCLUSIONS
In summary, this thesis offers an in-depth analysis of compliant mechanisms and their diverse applications It includes a detailed literature review that assesses the benefits and drawbacks of these mechanisms, highlighting the necessity for more advanced and optimized design solutions.
A compliant 2-DOF stage was designed and optimized through theoretical and RSM methods, followed by manufacturing and experimental testing to validate the analytical models and optimized parameters The findings confirmed that the proposed design exhibited enhanced performance, showcasing improvements in precision, stability, and accuracy.
The experiment aimed to validate simulation results and assess the performance of the proposed design against earlier models Findings indicated that the new design surpassed previous iterations and fulfilled the needs of diverse applications.
This thesis significantly advances the field of compliant mechanisms, showcasing their versatility for various engineering applications The introduced design and optimization method offers a valuable reference for future research and development efforts in this domain.
Compliant mechanisms represent a promising technology with significant potential in various engineering applications The insights gained from this thesis enhance the design and optimization processes of compliant mechanisms, setting the stage for future research and development in this innovative field.
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