REVIEW ON DESIGN OF COMPLIANT MECHANISM FOR AUTOMOTIVE APPLICATION A TOPLOGY OPTIMIZATION APPROACH

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 9, Issue 4, April 2018, pp , Article ID: IJMET_09_04_083 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed REVIEW ON DESIGN OF COMPLIANT MECHANISM FOR AUTOMOTIVE APPLICATION A TOPLOGY OPTIMIZATION APPROACH S.Premanand Brakes India Private Ltd, Polambakkam, India Dr.G.Arunkumar Professor and Head, Department of Mechanical Engineering, Sathyabama University,Chennai, India ABSTRACT This Paper Elucidates the Various Designs Involved in the Compliant mechanism which is merely applied in Various Applications of interdisciplinary Engineering Industries. The Compliant mechanism is centre to machinery and all Living organisms. In general, the Mechanism is defined as Transmission or Transformation of Force, motion, Energy. On basis of giving clarity about Compliant mechanisms we need to understand the basic two extremes of Design mechanisms, one extreme part is Machineries and its motion designs which turnouts into rigid bodies, Joint and Linkages which are stiffness in nature but transform/transmit into motions, another extreme is Structural designs (Ex: Bridges, Dams, Towers) which does not deform or move under loads applied on it. The Compliant mechanism designs acts as a spectrum between these two and has the property of structures and rigid body mechanism linkages. The Compliant mechanism has a structural design and has the mobility to Transform/Transmit Force, motion, Energy, Compliant mechanism is flexible and necessarily undergoes elastic deformation with a single structure without any joints or links. This type of designs is easy to manufacture by the 3D Printing Technology (Additive Manufacturing). This Review Paper narrates we are going to the cover the advanced designs of compliant mechanisms and its applications adaptable for engineering or Automotive Industries. Keywords: Compliant mechanism, Modern Kinematics, Topology Optimisation, Flexure hinges, Diaphragm, Vacuum assisted Booster, Automotive devices editor@iaeme.com

2 S.Premanand and Dr.G.Arunkumar Cite this Article: S.Premanand and Dr.G.Arunkumar, Review on Design of Compliant Mechanism for Automotive Application A Toplogy Optimization Approach, International Journal of Mechanical Engineering and Technology, 9(4), 2018, pp INTRODUCTION TO COMPLIANT MECHANISM ITS APPLICATIONS A flexible structure without joints or links that elastically deforms to produce a desired force or displacement. Compliant Mechanisms are elastic member that is used to transmit or transform Force, Energy and motion mechanically. Compliant Mechanisms is flexible or elastic mechanisms necessarily undergo Elastic Deformation. Compliant Mechanism Design is a Spectrum occupied between Structural Design and Rigid body mechanisms Design. In present industrial scenario manufacturing and assembly of micro mechanisms and its structures are found to be challenging. We have the opportunity of single component with flexibility and without rigid body linkages doing the same function of Rigid body mechanism, The usage of Compliant mechanisms design in place of rigid body mechanisms in engineering industries will have an advantage of reduction in Part Cost, weight and no of parts(bom). Flexible mechanisms with larger displacement will sort out many kinematics problems faced in engineering industry like MEMS, Medical Field, Surgical devices. The Current problem noticed in research point the design of Compliant mechanism is not materialized and directly suited or shall be fitted in any Engineering/Automobile applications, but this paper narrates the combination of methodologies adopted by the former researchers in this Compliant mechanism field for nonlinear motions and its output extent up to direct application in Engineering / Automotive applications. At Present the Compliant mechanism designs are widely used in the field of micro assembly systems, Medical Instruments and Invasive Surgeries, The former generation of Compliant mechanism design have focused on Macro and Micro kinematic applications streams but the recent researchers focus the compliant mechanism designs in Micro and Nano streams [2].By seeing the Micro manipulator designs of compliant mechanisms the parallel manipulators with five Limbs and one constraining limb are recent trending which their application is widely used in pick and place tools and robots [4]. Performance decomposition and Integration (PDI) is presently proposed for development of Design and Optimization of Compliant micro manipulators [4], Single Input with Single Output (SISO) is former design of Compliant mechanism in which it needs to prove only the force input vs output displacement, transmission of motion or energy, But the Compliant mechanism (SPCA) driven micro grippers are designed to prove the three relations, Linear input(spca) vs clamping movement (Kinematic model proving), Gripping force vs Strain angle of flexible hinges (static model proving) and finally control of gripping manipulation of micro grippers (Control strategy proving) [2]. These types of Micro Compliant Mechanism Grippers design find their application in Piezo electric and Magnetic Gripping tools in micro assembly systems [2]. Ratchet mechanism is prevalent not only in Automotive Industry (Centrifugal/Overrunning Clutches but also has applications in everyday engineering like Turnstiles, bicycle conveyor belts, zip ties, wrenches, etc. Amir HoseinSakhaei et al 2017, proposes a new compliant multi-material ratchet mechanism instead of a classical ratchet mechanism citing reasons such as [1] eliminating springs, reducing part count, and therefore easing of assembly, [2] elimination of space required for the global perpendicular motion of pawls during insertion, and [3] tuning of the mechanical behavior exploiting recent advances editor@iaeme.com

3 Review on Design of Compliant Mechanism for Automotive Application A Toplogy Optimization Approach in 3D Manufacturing Technology to replace traditional mechanisms with multi-material mechanisms Compliant Ratchet Mechanism (a) Linear ratchet (b) rotary ratchet Figure 1 Schematic diagram of the ratchet mechanism and its components Figure 2 Proposed Compliant Ratchet Mechanisms The schematic of performance of the proposed compliant ratchet mechanism; (a) starting of insertion step in linear direction, (b) during insertion step when the stiff tooth slides against each other and the flexible parts transfer the displacement of teeth to the localized elastic deformation, (c) upon the completion of the insertion step, the elastic deformation in flexible parts is recovered and the teeth are returned to the standing position and the mechanism can now work as an interlocking mechanism in the opposite direction, and (d) during locking process, how asymmetrical geometry of the teeth cause interlocking in the reverse direction COMPLIANT GRIPPER MECHANISM The traditional MIS (Minimally Invasive Surgery) tools design has a number of disadvantages for the surgeon, including decreased dexterity only four degrees of freedom, non-intuitive instrument control, poor vision, reduced force feedback, and poor ergonomics, which lead to editor@iaeme.com

4 S.Premanand and Dr.G.Arunkumar compromises in surgical technique. Complex movements, such as laparoscopic suturing, are thus extremely challenging and have a long learning curve. This has limited the variety of operations that can be completed with MIS. Although robotic instruments have six degrees of freedom of movement meaning that they have joints that can move in a manner similar to the human wrist, they have a number of limitations, such as lack of haptic force feedback, cumbersome size and weight of the system, and a cost of more than $1 million per system. In response to the above problems, S. Kota et al, proposed a compliant gripper mechanism for surgical tools. Compliant mechanisms incorporated into MIS Instruments enable precisely controlled completion of complex movements with natural or intuitive hand movements and haptic feedback. The monolithic nature of compliant mechanisms also has the advantage of no wear debris, no pinch points, and no lubrication, all of which are critical in the sensitive internal environment of the body. In addition, monolithic design simplifies the manufacturing and sterilization processes. Another advantage of compliant instruments is the built-in return spring action; a surgeon need only provide force in one direction to operate the device in both. At the same time, the spring action complicates the issue of force feedback. The surgeon will feel both the cutting/grasping force of the operation and the stiffness of the tool at the same time and may have difficulty differentiating between them. Figure 3 Prototype of the compliant gripper in its inactive mode (left) and gripping mode (right) 1.3. COMPLIANT CAR WIPER MECHANISM Reverse Engineering Process carried out for Study of Car wiper parts and Dimensional Data and the shape Compliant Wiper is optimized by Ansys to get Optimum Compliant design. Compliant wiper design is developed by replacing joints at datum wiper hence the component of wiper reduced to become Single Part only. COMPLIANT WIPER Figure 4 Compliant Wiper editor@iaeme.com

5 Review on Design of Compliant Mechanism for Automotive Application A Toplogy Optimization Approach 2. PROBLEM FORMULATION The problem is the design of a compliant mechanism Diaphragm in a vacuum suspended power booster Braking system coupled in which the input forces provided by a Push rod and pedal force. This compliant mechanism replaces the existing rubber reinforced metal structure, which amplifies the displacement and force of the power booster braking system. 3. OBJECTIVES OF OUR WORK To maximize the Geometric advantage (GA) Mechanical Advantage (MA) of the mechanism. To optimize the topology of the compliant mechanism using optimality criteria method. To design a compliant Diaphragm to multiply the amount of force applied to master cylinder by a factor greater than 3and also to achieve specific output displacement. Figure 5 Over view of Vacuum Assisted Boosters in Braking system The Power Booster increases the Force applied to the Master cylinder. If the Driver applies 5Kgf of force to the Brake Pedal and normally the mechanical advantage of the Pedal are 5 to 1 then there will be 25Kgf of force applied to the booster. In General, the Brake booster will multiply the force applied to the master cylinder by a factor between 2 and 3. That is if 20Kgf of force applied to the booster will turn into 40Kgf to 60Kgf and applies the force to the Master cylinder The Typical Vacuum booster has a Diaphragm with about 250 Square mm of surface area. With the Pressure differential of 10psi a force of 453Kgf can be developed editor@iaeme.com

6 S.Premanand and Dr.G.Arunkumar 4. OBJECTIVE FUNCTION & CONSTRAINT EQUATIONS A load f a applied at an input point a representing the input force from the strain actuator. The output deflection is equivalent to the mutual strain energy. Δ out = MSE = V b T K U a 1 The input deflection is obtained by assuming input load is a Unit load. Δ in = U a T K U a 2 Max (GA) = V b T K Ua / Ua T K Ua Constraint equations: f a = K Ua 3 f b = K Vb 4 Volume (V) V o Bounds on the design variables Mechanical advantage is defined as the ratio of output force by input force. Mechanical Advantage = F out / F in 4.1. SOLUTION METHODOLOGY I. Sequential Linear Programming (SLP) ( ii) Optimality Criteria method (OC) II. Method of moving asymptotes (MMA). Among these optimization methodologies the OC is chosen for our study, this is a best method to get Quick convergence topology design and to achieve desired result editor@iaeme.com

7 Review on Design of Compliant Mechanism for Automotive Application A Toplogy Optimization Approach Optimality criteria procedure Design Process 5. CONCLUSION I. The topology optimization method described in this work provides Vacuum Assisted Booster Diaphragm designers with a systematic method for design of compliant II. III. Diaphragm in Vacuum assisted Brake Booster This method is completely general in that any shape and size design domain and any combination of force and motion transformation from the Vacuum assisted Brake Booster output can be prescribed. It is possible to application of other type of boosters. The concept can be extended for other brake application parts in which the output is Displacement and Force amplification is required with Desired Geometrical and Mechanical advantage editor@iaeme.com

8 S.Premanand and Dr.G.Arunkumar ACKNOWLEDGEMENTS The author acknowledges those who have contributed in the field of elastic mechanisms for the betterment of Automotive, Engineering industry and society REFERENCES [1] Cristina Alonso, Ruben Angolaetal, Topology Synthesis of Multi Input Multi output Compliant Mechanisms, ,2014 Elsevier Ltd [2] Dapeng Zhang etal, Development of a monolithic compliant SPCA-driven micro gripper ,2014 Elsevier Ltd [3] Dhan Zhang, Zhen Gao, Performance analysis and Optimization of Five degree of Freedom Compliant Hybrid Parallel Manipulator ,2015 Elsevier Ltd [4] L.B.Tang,etal, Multi material compliant mechanism design and haptic evaluation, Volume 2, no, 3, ISSN print, online 2007 Taylor and francis [5] Jinyongjoo and Sridhar kota,topological synthesis of Compliant Mechanisms using Non Linear Beam Elements,Vol32,No,1,pp,17-38,2004 [6] G.Arunkumar, etal,compliant mechanisms by Topology Optimization Specific reference to new age industries and Engineering support [7] Howell L.L (2002), Design of Complaint Mechanisms Willey Publications, pp [8] D.S. Chan, Theory and implementation of multidimensional discrete systems for signal processing, doctoral diss., Massachusetts Institute of Technology, Cambridge, MA, [9] Ananthasuresh G.K.andAnupam Saxena (2003) A Computational Approach to the Number of Synthesis of Linkages, Journal of Mechanical Design, Transactions of ASME, Vol. 125, pp [10] Arun Kumar, and Srinivasan, PSS, (2006), Design of Displacement Amplifying Complaint Mechanism with integrated Strain Actuator using Topology Optimisation, International Journal of Mechanical Engineering Science, Vol.220, Issue 10, pp [11] Howell, LL and Midha, A, (2006) A method for the Design of Compliant Mechanisms with Small-Length Flexural Pivots, ASME Journal of Mechanical Design, Vol.116, pp [12] Kota, S and Hetrick, J, (2000), Synthesizing high-performance compliant stroke amplification systems for MEMS, Proceedings of the IEEE Micro Electro Mechanical systems, pp editor@iaeme.com