Robotic Manipulator for Positioning a Magnetic Actuator Dedicated to Drug Delivery in the Cochlea

International audienceThe actuators dedicated to micrometric applications are known for their precision but also for their restricted workspace. The use of a robotic manipulator as a carrier makes it possible to considerably increase this workspace. In this paper, we present a novel robotic system specially designed for positioning a magnetic actuator based on permanent magnets, used as an end-effector of the robot for steering magnetic microrobot throughout the cochlea. Using the classical mathematical tools of serial robotics, we determined the direct and inverse kinematic models of the manipulator, thus defining a reference trajectory to move the microrobot on a space as small as possible and take account of the geometrical specifications based on medical needs. A prototype has been realized with a 3D printer to experimentally validate the numerical results. In addition, the mechanical considerations for the construction of the prototype are presented

Design and Programming of 5 Axis Manipulator Robot with GrblGru Open Source Software on Preparing Vocational Students’ Robotic Skills

The rapid development of technology at the end of this decade, the industrial world is changing the human resources they have using the help of robot technology. The use of a robot was chosen because of the accuracy and precision that it can do in doing the job. In addition, robotic technology requires only one programming to do many things. Thus, there are many advantages for companies by using robotic technology in their production processes. This research aims to designing and building arm robot prototype to teach the robotics programming language. The result of this research is an arm robot prototype with Arduino Mega 2560 based programming. In addition, the robot movement programming uses the open source GrblGru software Grbl based. The GrblGru used for interpreting G-code and to convert pulse and direction information to control the stepper motor. This research concludes that there are 5 importance steps on develop the arm robot prototype, 1. Analyze; 2. Design; 3. Develop; 4. Evaluate; and 5. Implementation. With the GrblGru software the movements of arm robot prototype can work on simulation mode and control mode, there for students easier to study robotics programming language

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

AirCode: Unobtrusive Physical Tags for Digital Fabrication

We present AirCode, a technique that allows the user to tag physically fabricated objects with given information. An AirCode tag consists of a group of carefully designed air pockets placed beneath the object surface. These air pockets are easily produced during the fabrication process of the object, without any additional material or postprocessing. Meanwhile, the air pockets affect only the scattering light transport under the surface, and thus are hard to notice to our naked eyes. But, by using a computational imaging method, the tags become detectable. We present a tool that automates the design of air pockets for the user to encode information. AirCode system also allows the user to retrieve the information from captured images via a robust decoding algorithm. We demonstrate our tagging technique with applications for metadata embedding, robotic grasping, as well as conveying object affordances.Comment: ACM UIST 2017 Technical Paper

SIMULATION OF A ROBOTIC ARM FOR MULTI-DIRECTIONAL 3D PRINTING

The need to investigate new solutions and novel 3D building strategies not only requires the development of new slicing algorithms and the exploitation of machines with more than 3 Dofs, but also a safe and reliable test-bench to optimize all the phases of the process. The following article describes the assessment by simulation of suitable control architectures for the realization of a Fused Deposition Modeling printer based on a 6 Dofs serial manipulator. The focus is put on the obtained position and speed profiles for unidirectional and multi-directional 3D printing to determine the week points associated with each control strategy

Design of a Surgical Manipulator System for Lumbar Discectomy Procedures

A 3D printed surgical master-slave manipulator system for minimally invasive lumbar discectomy procedure is proposed. Discectomy is the surgery to remove the herniated disc material that is pressing on a nerve root or spinal cord. This surgery is performed to relieve pain or numbness caused by the pressure on the nerve. The workspace is limited (\u3c 27 cm3) and the manipulator has to go through a 3.175mm (0.125”) diameter channel. The proposed system is comprised of a family of manipulators that can work alone or co-operatively to perform tasks required in the surgery. In the proposed system, the manipulator is 3D printed with multiple materials, with flexible links acting as joints of the mechanism. These flexible links are actuated by cables which provide sufficient forces for actuation in the surgical workspace. In this thesis, existing surgical techniques are investigated and a new surgical system is proposed. Various design ideas are presented and evaluated for manufacturing and assembly. Finally, the proposed mechanisms are modeled and tested for their capability to assist the surgeon to perform tasks required for the surgery

Using Engineering to Create an Adaptive Self-Feeding System for Patients with Upper Body Disabilities

This research project aims to provide a self-feeding manipulator system to accommodate those who have upper-body motor disabilities. The purpose of the device is to allow patients to rely less on their caregivers during a meal. The patient's safe feeding without injury or malfunction at home or in a public setting will successfully achieve this form of assistance. The target cost is USD 1096 with a minimum of six months to make it a marketable product and nine months to develop a prototype. People have created similar devices such as the Neater Eater, Mealtime Partners, and the Obi Robotic Feeder in the past. These devices stem from one general need: provide a means to assist people with disabilities in feeding themselves. However, the disadvantage to all the existing products is that they are very costly, ranging between 4000 – 8000 USD apiece. In addition, they are inaccessible to people in Qatar due to their production and market being overseas. We use engineering methods to create a device that is more versatile and accessible. This thesis discusses all the alternatives created to build the manipulator. The manipulator's design is one with four degrees of freedom, and the actuators used to mobilize the joints were Servo Motors. The manipulator is to work automatically using Denavit-Hartenberg, Forward Kinematics, and Jacobian robotics methods. Some parts of the manipulator require 3D printing and CNC machining, which will be accessible in the TAMUQ building. In addition, some parts will be bought based on our requirements calculations. Another engineering method used to control the manipulation of the system is by using an Arduino board. The device consists of four main subsystems. Firstly, there is the base which mounts on any flat surface. Also, a plate, divided into four sections, that attaches to the base and can rotate. The manipulator is also attached to the base, along with a spoon attached to the manipulator. Finally, the user-interface is a critical component of the system to allow easy communication between the user and the device. Since this device targets patients with upper-body disabilities, a user-interface that functions using the patient's feet would be suitable. We aim to have the device ready to test by the end of April 2021 and allow patients from Sidra Hospital to test the device

An innovative machine for Fused Deposition Modeling of metals and advanced ceramics

The design of a new additive manufacturing (AM) system based on extrusion and 3D deposition of a mixture of metal (or advanced ceramic) powder and polymeric binder is described in this paper. The proposed system is totally innovative in terms of combination of deposited work material, extrusion system (head and nozzle), and deposition work table, which is based on a 5-axes parallel kinematics machine (PKM). The extrusion head and nozzle have been designed in order to be able to extrude high viscosity mixtures with low polymeric content. The 5-axes PKM is aimed at obtaining a good surface quality of the deposited work and reducing the need for supports during deposition. After the deposition, the material is de-binded and sintered to nearly the density of the solid material as-cast. The design and kinematics of the machine and especially the PKM table is described in this paper, the main design issues are discussed and some preliminary extrusion and sintering results are presented