Giancarlo Facoetti

A digital patient for computer-aided prosthesis design

This article concerns the design of lower limb prosthesis, both below and above knee. It describes a new computer-based design framework and a digital model of the patient around which the prosthesis is designed and tested in a completely virtual environment. The virtual model of the patient is the backbone of the whole system, and it is based on a biomechanical general-purpose model customized with the patients characteristics (e.g. anthropometric measures). The software platform adopts computer-aided and knowledge-guided approaches with the goal of replacing the current development process, mainly hand made, with a virtual one. It provides the prosthetics with a set of tools to design, configure and test the prosthesis and comprehends two main environments: the prosthesis modelling laboratory and the virtual testing laboratory. The first permits the three-dimensional model of the prosthesis to be configured and generated, while the second allows the prosthetics to virtually set up the artificial leg and simulate the patients postures and movements, validating its functionality and configuration. General architecture and modelling/simulation tools for the platform are described as well as main aspects and results of the experimentation.

A full virtual approach to design and test lower limb prosthesis

Lower limb prostheses for above or below knee amputees are still designed and produced almost completely in a manual way, deeply relying on the experience and manual skills of orthopaedic technicians. This paper presents the main features characterising the prototype of a virtual environment developed to assist the technicians designing and testing the prosthesis. To reach the ambitious goal of replacing the manual process with a complete virtual one several issues have been considered and addressed: the capture and formalisation of process knowledge of orthopaedic technicians, the acquisition of patients information and digital data, the development of an integrated solution to design and test standard and custom-fit components and the simulation of the gait of a virtual human wearing the virtual prosthesis. The architecture of the prosthesis design platform as well as the modelling and simulation tools are described. Finally, the experimentation phase and related results are presented and discussed.

Socket virtual design based on low cost hand tracking and haptic devices

This paper concerns a research project that aims at developing an innovative platform to design lower limb prosthesis. The platform is centered on the virtual model of the amputee and is based on a computer-aided and knowledge-guided approach. In particular, the paper focuses on the module, named Socket Modeling Assistant-SMA, conceived to design the socket, the most critical component of the whole prosthesis. The underlining idea is to experiment low-cost devices, such the Leap Motion, to manipulate the 3D virtual model of the socket using hands as traditional done by the prosthetist. The goal is to make available a modeling tool that permits to replicate/emulate manual operations usually performed by the prosthetist during the traditional development process. First, we first describe the traditional socket development process; then the SMA software architecture and the guidelines used to develop the interaction algorithms (integrated within SMA) that exploit the Leap Motion and Falcon devices. Finally preliminary tests and results will be illustrated.

An environment for contrast-based treatment of amblyopia using 3D technology

We have developed an application based on binocular vision for amblyopia treatment. It is founded on stereo vision of objects with different contrast. Fellow eye occlusion does not allow a binocular vision but only a monocular one. This approach causes brain skills loss like the perception of depth. Our system increases visual acuity for amblyopic patients using binocular vision. Binocular vision shows an object to each eye with different contrast. In fact, if we apply a right contrast ratio between amblyopic eye and lazy eye, then amblyopic patient is able to perceive both.

Mixed reality to design lower limb prosthesis

This paper presents a Mixed Reality environment, named Virtual Orthopedic LABoratory (VOLAB), which permits to emulate an orthopedic lab and design lower limb prosthesis, in particular, the socket component. The proposed solution is based on low cost devices (e.g., Microsoft Kinect) and open source libraries (e.g., OpenCL and VTK). In detail, the hardware architecture consists of three Microsoft Kinect v2, Oculus Rift for 3D environment visualization and Leap Motion device for hand/fingers tracking. The software development has been based on the modular structure of the prosthetic CAD system, named Socket Modelling Assistant (SMA) and modules have been developed to guarantee the communication among the devices and the performance. Finally, preliminary tests are illustrated as well as results reached so far and future development.

Automatic 3d reconstruction of transfemoral residual limb from MRI images

This work is part a new design platform for lower limb prosthesis centered on the patients digital model and based on the integrated use of virtual prototyping tools. In particular, 3D detailed model of residual limb, that includes not only the external skin but also bones and soft tissues, is needed for socket design and finite element analysis to study the socket-residual limb interaction. In this paper, we present a procedure for 3D automatic reconstruction of the residual starting from MRI images. The output is a 3D geometric model, in a neutral format (IGES), which permits CAD information exchange among the modules composing the design platform. The reconstruction procedure consists of three different phases: image pre-processing, voxel segmentation, 3D models generation. Results have been considered promising and future activities to enhance the algorithm performance have been planned.

Automatic Generation of Software Interfaces for Hand-Tracking Devices

This paper presents a software module, named tracking plug-in, developed to automatically generate the source code of software interfaces for managing the interaction with low cost hand-tracking devices (e.g., Leap Motion and Intel Gesture Camera) and replicate/emulate manual operations usually performed to design custom-fit products, such medical devices and garments. The proposed solution is based on the Eclipse platform, a free integrated development environment (IDE), that allow us to manage the automatic code generation in a simple way after having defined the target application using a meta-model language, in our case the UML class diagram. First, we describe the background as well as the main problem, then, the software solution and adopted tools (i.e., Eclipse and Acceleo). Finally, the preliminary tests carried out for two applicative contexts (prosthetic and textile/clothing) are presented.Copyright

SimplyNURBS: A Software Library to Model NURBS for Medical Applications

ABSTRACTCustom-fit products, such as artificial prostheses, often require the development of hoc modeling tools and procedures. In such a context, this paper describes an open source library, named SimplyNURBS, developed for NURBS modeling in medical and health-care domains. This new suite makes available a development kit that integrates the key features of existing open source libraries and new ones to fulfill the requirements of the considered domain. First, the paper introduces the library requirements with particular attention to the prosthetic field as well as pros and cons of current NURBS modeling libraries (both commercial and open sources). Then, the software architecture of SimplyNURBS and the basic libraries (e.g., OPENCASCADE and NURBS++) used for its implementation are illustrated enhancing differences and improvements. Finally, a socket modeling tool, named Virtual Socket Laboratory (VSL) developed using SimplyNURBS is described as well as results of tests carried out to evaluate the new sy...

A preliminary study of new interaction devices to enhance virtual socket design

This paper presents a research work on the augmented interaction applied to an innovative platform to design lower limb prosthesis, in particular the prosthetic socket. The underlining idea is to experiment low-cost hand-tracking devices, to manipulate the 3D virtual model of the socket using hands as traditional done by the prosthetist. The goal is to make available a modeling tool, named Socket Modeling Assistant SMA that permits to replicate/emulate manual operations usually performed by the prosthetist during the traditional development process. Two devices have been considered and compared: the Leap Motion device and the Intel Gestures Camera. To this end a set of gestures has been identified to make more natural the interaction with SMA. Preliminary tests and results reached so are described and discussed.

A Virtual Human for Lower Limb Prosthesis Set-Up

This paper concerns the usage of virtual humans to validate lower limb prosthesis design. In particular, we are developing an innovative design framework centered on digital models of the whole patient or of his/her anatomical districts, which constitute the backbone of the design process. The framework integrates a set of virtual “assistants” to guide the technicians during each design task providing specific knowledge and design rules. In this paper, we focus the attention on the last step of the prosthesis deign process, i.e., the final set-up with the patient using a biomechanical model of the amputee. First, we describe the state of art on virtual humans and main features of the new design framework. Then, the application of virtual humans for the prosthesis set-up is presented as well as preliminary results.Copyright