Robotic manipulator for dental applications

Dr Wang, Zheng   (Principal Investigator (PI))

Dr Pow Edmond Ho Nang   (Co-Investigator)

Dr Lam Yu Hang Walter   (Co-Investigator)

12

2017-06-01

150000

Robotic manipulator for dental applications

Dental surgery, Robot manipulator, Robotics, Surgical robots

Robotics and Automation,Design

Engineering (E)

201611160034

Seed Fund for PI Research – Translational and Applied Research

2016

Completed

Robotic surgery is a rapidly emerging research area. Within the past two decades, a billion-dollar market has been created from scratch, with over 4000 surgical robot stations installed worldwide, and over 3 million robot-assisted surgical procedures had been carried out on patients. This on one hand stimulated global research interest in surgical robotic technology, while on the other hand pushes the research frontier in multiple related disciplines regarding how to bring better and more efficient healthcare service to end-patients. The strong relevance to patients’ health and the high financial profits also make surgical robotics a highly active and highly competitive research field with global attention and recognition. Dental health is closely related to the life quality of people. Hong Kong has one of the world’s longest-living population, therefore has a very large group of patients with dental conditions. Hong Kong is world leading for its high standards in dental care, both for clinical practice and for research and education, with HKU Faculty of Dentistry in particular, as one of the top institutions in global rankings. On the other hand, the dental practice in reality is facing a very serious challenge of labor shortage, as the education and training of young generation dental clinicians cannot cope with the rapidly increasing patient need. Robotics is a promising solution, both to relieve labor shortage by automating parts of the dental procedure, and to improve dental care quality delivered to the patients. In fact, dental robots have already been developed worldwide over the past decade, following the vast success of renal and general surgical robots. However, dental procedures have their own set of characteristics differing substantially from other surgical procedures, therefore call for specific robotic solutions different from existing surgical robots: - [Dimensions and workspace]. Dental robots that operate within the oral cavity could enter through the open mouth, therefore they are not subject to the tight spatial constrains applied on surgical robots passing through key-hole-size incisions in laparoscopic procedures; the minimum workspace requirement is also limited to the size of one tooth, both for crown and gum treatments. - [Procedure and instruments]. Different from other surgical procedures, dental treatments are mostly carried out to prevent or treat dental caries and pyorrhea, the two most common oral diseases. Such treatments involve both distinctive procedures and specialized instruments, resulting in unique specifications and requirements on the dental robotic systems. - [Rigidity and precision]. For crown treatments, the dental robot need to drill into the crown material, which is hundreds of times more rigid than the soft tissues dealt by surgical robots; the high speed drilling end-effector also calls for very high torque and precision (<0.1mm) to guarantee good results. - [Dexterity and control]. Due to the fixed location of each tooth, the dental robot must be able to reconfigure itself dexterously within the oral cavity, in order to sufficiently reach necessary location and orientations for the treatment. This calls for more Degrees-of-Freedom (DoF) than any existing surgical robot systems. The new increased dexterity also requires advanced level of control from dental surgeons to operate effectively. Existing dental robots are mainly rooted from industrial robot manipulators with similar dimensions of the human arm. Some existing work directly program industrial arms to use in dental procedures; others develop specific devices with comparable size and structure. Based on the above discussion on the distinctions of dental robots, such devices are not ideal in performing dental treatments, and they take up a substantial amount of space in the clinic, with premium costs both for system installation and per-treatment consumables. In this project, we propose a novel approach to dental robot systems. We depart from industrial manipulators, and develop a novel robot manipulator specifically for dental applications from scratch. The main objectives of this project is listed below: 1. Analysis of robotic manipulator kinematics for the human oral cavity. We will first conduct a systematic analysis on the workspace of the robot based on the features of human oral cavity, and derive the appropriate kinematic structures for the dental robot. This will allow us to design the dental-specific robotic manipulator matching the oral environment. 2. Design and development of the finger-sized dental robot. Based on the analysis, we will design and develop a dental robot manipulator remarkably smaller than existing human arm-sized dental robots. The new dental robot will be of comparable size with a human finger, but it will have sufficient workspace to maneuver inside the oral cavity and reach even the deepest corner for treatments. The new arm will have 7 DoF, with comparable dexterity with the human arm. This will allow the robot to reconfigure itself to avoid obstacles and reach difficult angles even for clinicians. 3. Control and system integration of the dental robot. In addition to mechanical design, we will also develop the corresponding actuation and control systems, to enable doctors to operate the robot intuitively. Each joint of the robot will be controlled independently, with an overall high level algorithm taking charge of automatic mapping and motion compensation. Automatic features will be explored for programming the robot to follow pre-defined trajectories. The project is highly feasible within the time scale and resources. The PI has rich experiences in developing, fabricating, and testing robotic devices for medical applications. The co-Is are world class prosthodontic dentists with rich experiences of clinical practice. The new dental robot arm will be based on the miniature surgical robot arms previously developed by us for endoscopic procedures with proven superior performance. Given the limited scope and resources of this seed project, we will focus on the engineering development, in order to develop a prototype which can be used in applying external grants. Clinical studies with animal or human models will not be covered in this stage of the project.