Haptic-Enabled Mobile Robotics: Acceleration Based Viarable Force Feedback in Obstacle-Avoidance Task
Members:Kalanathlalith Gunturu, Nicolas Cramer, David Racine, & Mehrdad Zadeh.
Motivatiuon: Obstacle avoidance is a very important task in the navigation of mobile robotics. We here deal with human in the loop as the robot is controlled by a tele-operator. The lack of perceprion of the environment reduces the effectiveness of the operator. To increase the awareness of the operator, haptic effects are routinely added. We investigate the effects of using force feedback steering wheel and haptic gas pedal in an obstacle avoidance task.
Application: most of the mobile robot tele-operation tasks are evaluate based on the perceprion of the operator in the remote location. They involve controlling of the robot with joystick like devices. The inclusion of steering wheel and gas pedal in to this system is for the more ergonomic feasibility standpoint. Also, the integration of haptic effects on steering wheel and gas pedal augment the driving task. The haptic feedback better assist in maneuvering the robot in obstacle avoidance task.
Task: Twenty subjects were seated in front of the track. They were asked to control the robot by holding the steering wheel with their hands and control forward motion of the steering wheel with their hands and control forward motion of the robot with pedal under their feet. They needed to maneuver the robot in the exact path labeled on the floor. The haptic force feedback was provided on steering wheel and haptic gas pedal to provide the relative position of obstacles on the track. Also, they were asked to finish the task without haptic assistance for evaluation of haptic effect. During the completion of the task, students would be assisted by the force feedback on the directions of steering wheel based on position of obstacle relative to the robot. In addition, force feedback on foot of the operator would be provided through the haptic pedal.
Fig 1. Operator controls the teleoperated robot via force feedback provided by steering wheel and pedal
Providing Haptic Feedback in Robot-Assisted Minimally Invasive Surgery: A Direct Optical Force Sensing Solution for Haptic Rendering of Deformable Bodies
Members: Shervin Ehrampoosh, Reza Yousefian, Mohit Dave, Mohamed Elnaggar, Jacob Nangle, Raniel Ornelas, Pedro Henrique Affonso, Garret Kottmann, Dr. Micheal Kia, and Dr. Mehrdad Zadeh.
Motivation: Advances in minimally invasive surgery (MIS) has considerably progressed in the recent years. However, certain limitations still exist. A major shortcoming of MIS, and one that has been the subject of this research, is the lack of sensory information from the operative field available to the surgeon, resulting in a reduced access between the surgeon and the tissue.Although advances in master-slave robot-assisted surgery have improved accuracy and dexterity in comparison with open surgery, however, an effective haptic feedback is still missing from robots. This loss of force feedback leads to excessive or even insufficient forces that would increase damage to well tissue or even slippage in grasping, leading to loss of control. In addition, it would be difficult to palpate or assess tissue characteristics. As a result, force sensing could lead to expand safety and diminished intraoperative time, and it could help less experienced surgeons to do complex surgeries with less practice.
Method: In this study, a bilateral master-slave tele-manipulation is presented with parallel force-position control architecture, as shown in Fig.2. In this method, two Phantom Omnis are directly assigned as master-slave devices to connect the human and environment commands into the teleoperation system. In the slave side, a proposed optical force sensor designed and prototyped to provide direct contact force measurement for the interaction forces between the environment and the slave device. Three optical fibers transmit and receive light while the reflector is axially moved. The system architecture is based on position error (PEB) and direct force reflection (DFR).
Fig.2. Block diagram of the parallel force/position architecture.
Result: Two experiments were conducted to examine the potential effects of force feedback in the proposed MIS teleoperation system. The equipments including three deformable objects like: a sponge, suturing pad, and a model organ as high, medium, and low deformable objects, as well as a box which is used for surgeons to practice minimally invasive surgery. The contents of the box are obstructed to allow for testing just the effect of haptic feedback. The master-slave setup for performing teleoperation is shown in Fig. 3.
Fig. 3. Experimental Master-slave setup for the tele-operation system.
First, twenty subjects were randomly chosen to feel three materials which were put in a surgical box, using a laparoscopic tool directly. The purpose of this experiment was to define how accurate people detect deformability of the objects to assess it as a base data in teleoperation. After that, another ten subjects were randomly chosen to run the master-slave system to feel the objects. For each material, a different value of PD controller would change the type of feedback allowing the user to distinguish each object. This experiment was done with and without haptic feedback. By comparing the results, the values for PD controller are exactly matched with the direct measurement.
Automated Ligation Device for Laparoscopic Surgery
Members: Reza Yousefian, Paul Jones, Christopher Barnard, Lucas Bell, Daniel Gudorf, Shervin Ehrampoosh, & Mehrdad Zadeh.
Abstarct: The objective of this project is to occlude a vessel using a suture and repeat the process several times. This device is needed because the only alternative method which is using staples has multiple disadvantages such as taking up a great deal of space behind the vessel. In order for a laparoscopic stapling device to work the surgeon needs to move the tool several millimeters behind the vessel. Many vessels do not have the required space behind them. This forces surgeons to pull on the vessel, which could damage it, and force the device past it. Our device will not require as much space behind the vessel, so it will reduce the risk of damage. Also, when using a laparoscopic stapling device it is possible that the vessel will move beyond the staple while it is being clamped down upon by the stapling jaw. (More information is confidential because of the final report patent due date)
Fig 4. Device structure
Dr. Zadeh can be contacted by:
Phone: (810) 762-9500, Ext. 5914
Fax : (810) 762-9830
Office: AB 2-703-P
Kettering University1700 University Avenue
Flint, Michigan 48504