We report on a structured light-scanning system, the OGX|4DSCANNER, capable of capturing the surface of a human body with 2 mm spatial resolution at a 60 Hz frame-rate. The performance of modeling the human lower body dynamics is evaluated by comparing the system with the current gold standard, i.e., the VICON system. The VICON system relies on the application of reflective markers on a person’s body and tracking their positions in three-dimensional space using multiple cameras [optical motion capture (OMC)]. For the purpose of validation of the 4DSCANNER, a set of “virtual” markers was extracted from the measured surface. A set of musculoskeletal models was built for three subjects based on the trajectories of real and virtual markers. Next, the corresponding models were compared in terms of joint angles, joint moments, and activity of a number of major lower body muscles. Analyses showed a good overall agreement of the modeling outcome. We conclude that the 4DSCANNER within its limitations has the potential to be used in clinical gait analysis instead of optical marker-based systems. The advantage of the 4DSCANNER over OMC solutions is that it does not burden patients with time-consuming marker application. This study demonstrates the versatility of this measurement technique.
We present a human-computer interface that enables the operator to plan a surgical procedure on the musculoskeletal
(MS) model of the patient's lower limbs, send the modified model to the bio-mechanical analysis module, and export the
scenario parameters to the surgical navigation system. The interface provides the operator with tools for: importing
customized MS model of the patient, cutting bones and manipulating/removal of bony fragments, repositioning muscle
insertion points, muscle removal and placing implants. After planning the operator exports the modified MS model for
bio-mechanical analysis of the functional outcome. If the simulation result is satisfactory the exported scenario data may
be directly used during the actual surgery.
The advantages of the developed interface are the possibility of installing it in various hardware configurations and
coherent operation regardless of the devices used. The hardware configurations proposed to be used with the interface
are: (a) a standard computer keyboard and mouse, and a 2-D display, (b) a touch screen as a single device for both input
and output, or (c) a 3-D display and a haptic device for natural manipulation of 3-D objects.
The interface may be utilized in two main fields. Experienced surgeons may use it to simulate their intervention plans
and prepare input data for a surgical navigation system while student or novice surgeons can use it for simulating results
of their hypothetical procedure.
The interface has been developed in the TLEMsafe project (www.tlemsafe.eu) funded by the European Commission FP7
Currently, a lot of different scanning techniques are used for 3D imaging of human body. Most of existing systems are
based on static registration of internal structures using MRI or CT techniques as well as 3D scanning of outer surface of
human body by laser triangulation or structured light methods. On the other hand there is an existing mature 4D method
based on tracking in time the position of retro-reflective markers attached to human body. There are two main drawbacks
of this solution: markers are attached to skin (no real skeleton movement is registered) and it gives (x, y, z, t) coordinates
only in those points (not for the whole surface). In this paper we present a novel multidirectional structured light
measurement system that is capable of measuring 3D shape of human body surface with frequency reaching 60Hz. The
developed system consists of two spectrally separated and hardware-synchronized 4D measurement heads. The principle
of the measurement is based on single frame analysis. Projected frame is composed from sine-modulated intensity
pattern and a special stripe allowing absolute phase measurement. Several different geometrical set-ups will be proposed
depending on type of movements that are to be registered.