DESIGN OF THREE FINGER GRIPPER WITH FSR

Technological advancement is widening up by the advent of new inventions. Robots are going to be an integral part of the completely automated industries. There are many instances where profile detection. In this paper, discussed about the three finger gripper has the abilities with this dexterous electric gripper. Three fingers gripper is extreme changeability and fixable gripping control. Its finger has several positions of geometrics and dimensions. Its specific control of crossing point allows orthodox forward motion on the finger location, rapidity and force. These fingers design in CREO 3.0 software and produced by RPT. Fingers are evaluated to check if the finger is flexible motion. The force is measured by a force sensitive resister (FSR). A force sensor is measure a grasping object whose confrontation difference between before and after force is applied. The Arduino mega controller is used for controlling the servo motor and FSR in gripping motion. This servo motor is 180Ëšrotation angle, Control loop response mechanism is extensively used for accurate control. The Controlled gripper finger is sensed and gripped with force which is being analyzed in the data

Part clamping and fixture geometric adaptability for reconfigurable assembly systems.

Masters of Science in Mechanical Engineering. University of KwaZulu-Natal. Durban, 2017.The Fourth Industrial Revolution is leading towards cyber-physical systems which justified research efforts in pursuing efficient production systems incorporating flexible grippers. Due to the complexity of assembly processes, reconfigurable assembly systems have received considerable attention in recent years. The demand for the intricate task and complicated operations, demands the need for efficient robotic manipulators that are required to manoeuvre and grasp objects effectively. Investigations were performed to understand the requirements of efficient gripping systems and existing gripping methods. A biologically inspired robotic gripper was investigated to establish conformity properties for the performance of a robotic gripper system. The Fin Ray Effect® was selected as a possible approach to improve effective gripping and reduce slippage of component handling with regards to pick and place procedures of assembly processes. As a result, the study established the optimization of self-adjusting end-effectors. The gripper system design was simulated and empirically tested. The impact of gripping surface compliance and geometric conformity was investigated. The gripper system design focused on the response of load applied to the conformity mechanism called the Fin Ray Effect®. The appendages were simulated to determine the deflection properties and stress distribution through a finite element analysis. The simulation proved that the configuration of rib structures of the appendages affected the conformity to an applied force representing an object in contact. The system was tested in real time operation and required a control system to produce an active performance of the system. A mass loading test was performed on the gripper system. The repeatability and mass handling range was determined. A dynamic operation was tested on the gripper to determine force versus time properties throughout the grasping movement for a pick and place procedure. The fluctuating forces generated through experimentation was related to the Lagrangian model describing forces experienced by a moving object. The research promoted scientific contribution to the investigation, analysis, and design of intelligent gripping systems that can potentially be implemented in the operational processes of on-demand production lines for reconfigurable assembly systems

Development of novel micropneumatic grippers for biomanipulation

Microbjects with dimensions from 1 μm to 1 mm have been developed recently for different aspects and purposes. Consequently, the development of handling and manipulation tools to fulfil this need is urgently required. Micromanipulation techniques could be generally categorized according to their actuation method such as electrostatic, thermal, shape memory alloy, piezoelectric, magnetic, and fluidic actuation. Each of which has its advantage and disadvantage. The fluidic actuation has been overlooked in MEMS despite its satisfactory output in the micro-scale. This thesis presents different families of pneumatically driven, low cost, compatible with biological environment, scalable, and controllable microgrippers. The first family demonstrated a polymeric microgripper that was laser cut and actuated pneumatically. It was tested to manipulate microparticles down to 200 microns. To overcome the assembly challenges that arise in this family, the second family was proposed. The second family was a micro-cantilever based microgripper, where the device was assembled layer by layer to form a 3D structure. The microcantilevers were fabricated using photo-etching technique, and demonstrated the applicability to manipulate micro-particles down to 200 microns using automated pick-and-place procedure. In addition, this family was used as a tactile-detector as well. Due to the angular gripping scheme followed by the above mentioned families, gripping smaller objects becomes a challenging task. A third family following a parallel gripping scheme was proposed allowing the gripping of smaller objects to be visible. It comprises a compliant structure microgripper actuated pneumatically and fabricated using picosecond laser technology, and demonstrated the capability of gripping microobject as small as 100 μm microbeads. An FEA modelling was employed to validate the experimental and analytical results, and excellent matching was achieved

Overview of microgrippers and design of a micro-manipulation station based on a MMOC microgripper

International audienceThis paper deals with an overview of recent microgrippers. As the end-effectors of micromanipulation systems, microgrippers are crucial point of such systems for their efficiency and their reliability. The performances of current microgrippers are presented and offer a stroke extending from 50 m to approximately 2mm and a maximum forces varying from 0,1mN to 600 mN. Then, micromanipulation system based on a piezoelectric microgripper and a SCARA robot is presented

Workshop on "Control issues in the micro / nano - world".

International audienceDuring the last decade, the need of systems with micro/nanometers accuracy and fast dynamics has been growing rapidly. Such systems occur in applications including 1) micromanipulation of biological cells, 2) micrassembly of MEMS/MOEMS, 3) micro/nanosensors for environmental monitoring, 4) nanometer resolution imaging and metrology (AFM and SEM). The scale and requirement of such systems present a number of challenges to the control system design that will be addressed in this workshop. Working in the micro/nano-world involves displacements from nanometers to tens of microns. Because of this precision requirement, environmental conditions such as temperature, humidity, vibration, could generate noise and disturbance that are in the same range as the displacements of interest. The so-called smart materials, e.g., piezoceramics, magnetostrictive, shape memory, electroactive polymer, have been used for actuation or sensing in the micro/nano-world. They allow high resolution positioning as compared to hinges based systems. However, these materials exhibit hysteresis nonlinearity, and in the case of piezoelectric materials, drifts (called creep) in response to constant inputs In the case of oscillating micro/nano-structures (cantilever, tube), these nonlinearities and vibrations strongly decrease their performances. Many MEMS and NEMS applications involve gripping, feeding, or sorting, operations, where sensor feedback is necessary for their execution. Sensors that are readily available, e.g., interferometer, triangulation laser, and machine vision, are bulky and expensive. Sensors that are compact in size and convenient for packaging, e.g., strain gage, piezoceramic charge sensor, etc., have limited performance or robustness. To account for these difficulties, new control oriented techniques are emerging, such as[d the combination of two or more ‘packageable' sensors , the use of feedforward control technique which does not require sensors, and the use of robust controllers which account the sensor characteristics. The aim of this workshop is to provide a forum for specialists to present and overview the different approaches of control system design for the micro/nano-world and to initiate collaborations and joint projects

Development and Force/Position control of a new Hybrid Thermo-Piezoelectric MicroGripper dedicated to micromanipulation tasks.

International audienceA new microgripper dedicated to micromanipulation and microassembly tasks is presented in this paper. Based on a new actuator, called thermo-piezoelectric actuator, the microgripper presents both a high range and a high positioning resolution. The principle of the microgripper is based on the combination of the thermal actuation (for the coarse positioning) and the piezoelectric actuation (for the fine positioning). In order to improve the performances of the microgripper, its actuators are modeled and a control law for both the position and the manipulation force is synthesized afterwards. A new control scheme adapted for the actuators of the hybrid thermo-piezoelectric microgripper is therefore proposed. To prove the interest of the developed microgripper and of the proposed control scheme, the control of a pick-and-release task using this microgripper is carried out. The experimental results confirm their efficiency and demonstrate that the new microgripper and the control law are well suited for micromanipulation and microassembly applications

Flexible micro-assembly system equiped with an automated tool changer.

International audienceThis paper deals with the design, fabrication and experimental validation of several modules of a micro-assembly system. On one hand, a microgripper is integrated in a four degrees of freedom system. On the other hand, a tool changer is designed. It enables to exchange automatically the tip part of the microgripper and then dedicated tools can be used to achieve specific tasks. The principle of this tool changer relies on a thermal glue whose phase (liquid or solid) is controlled by heat generators. This system is based on the modeling of thermal phenomena in the tools during a cycle of tool exchange. A compliant system is added to limit micromanipulation forces applied during assembly tasks like insertions. Finally, the successful assembly of several microcomponents is detailed, highlighting the capabilities and benefits of the whole system

Scalability study for robotic hand platform

The goal of this thesis project was to determine the lower limit of scale for the RIT robotic grasping hand. This was accomplished using a combination of computer simulation and experimental studies. A force analysis was conducted to determine the size of air muscles required to achieve appropriate contact forces at a smaller scale. Input variables, such as the actuation force and tendon return force, were determined experimentally. A dynamic computer model of the hand system was then created using Recurdyn. This was used to predict the contact (grasping) force of the fingers at full-scale, half-scale, and quarter-scale. Correlation between the computer model and physical testing was achieved for both a life-size and half-scale finger assembly. To further demonstrate the scalability of the hand design, both half and quarter-scale robotic hand rapid prototype assemblies were built using 3D printing techniques. This thesis work identified the point where further miniaturization would require a change in the manufacturing process to micro-fabrication. Several techniques were compared as potential methods for making a production intent quarter-scale robotic hand. Investment casting, Swiss machining, and Selective Laser Sintering were the manufacturing techniques considered. A quarter-scale robotic hand tested the limits of each technology. Below this scale, micro-machining would be required. The break point for the current actuation method, air muscles, was also explored. Below the quarter-scale, an alternative actuation method would also be required. Electroactive Polymers were discussed as an option for the micro-scale. In summary, a dynamic model of the RIT robotic grasping hand was created and validated as scalable at full and half-scales. The model was then used to predict finger contact forces at the quarter-scale. The quarter-scale was identified as the break point in terms of the current RIT robotic grasping hand based on both manufacturing and actuation. A novel, prototype quarter-scale robotic hand assembly was successfully built by an additive manufacturing process, a high resolution 3D printer. However, further miniaturization would require alternate manufacturing techniques and actuation mechanisms