The CAREN project stands for the development of Computer Assisted Rehabilitation Environments, operating in Real-Time domain. It concerns the development of a virtual reality system in which the balance behaviour of humans can be tested in a variety of reproducible conditions.
The major objective of the project is to enhance (early) diagnostic and therapeutic activities in a range of medical fields by decreasing the time needed for successful rehabilitation programs. The enhancements are defined by allowing a medical expert team the opportunity to view and analyse balance and coordination movement patterns as they happen in a controlled real-time environment. This will enable the expert panel to immediately intervene and correct the patient’s behaviour.

CAREN is a system, which consists of a combination of a Motion Platform, a 3D video projection, Motion Capture of the patient and a Graphics workstation. Most European rehabilitation clinics use specialized therapeutic programs, based on cause related classifications of movement disorders, but there is no network communicative protocol available to exchange medical experiences on used equipment and procedures. This has inspired MOTEK to develop an interactive virtual Real-Time computer driven applied tool-platform, which can provide patients with means of almost unlimited exploratory behaviours. At the same time provide medical experts accurate measurement tools for monitoring progress in the rehabilitation process.

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CAREN is made by customizing hardware and developing software to enable measurements of motion of a patient in detail, as a response to a perturbation from the computer driven platform.
The movements of the platform are performed in close synchrony with the projected images on the video screen and can be independent of the movements of the patient or co-dependent of the movements of the patient. The inverse dynamics simulations are performed with a 15 segments 3D human body model (Motion Capture). The simulations reconstruct the moments of force, produced around the joints of the patient. The joints depend in their turn on muscle activation. Especially in complex balance tasks, the patterns of muscle activation determine whether a patient falls or not. These simulations are aimed at an understanding and evaluation of normal or pathological response patterns in certain balance tasks. The forward dynamic simulations can be done at any time during an inverse dynamic simulation. The flow of movements as an input to the inverse dynamic simulation is stopped during the sequence and the calculated joint movements are now used as input, while the movements become output.

The current CAREN system combines the following elements:

Hardware:

Optical Motion Capture system

Electromagnetic tracking devices

Multi-CPU hardware platform

A 6 Degrees of Freedom (DOF) Motion platform

Control computer with dual head option and video I/O.

Software:

The CAREN software system, called D-FLOW®, is the heart of the CAREN project. The D-FLOW® technology is the first technology to provide a Real-Time feedback loop between a Motion-Tracker and a Motion-Platform. This allows, for example, a doctor to place a patient with Parkinson into the D-FLOW® system and compensate for tremors, which have prevented the patient from standing still.
Video screen and 3D shutter glasses: The visual part of the environment is projected in 3D on the video screen in front of the patient, wearing 3D shutter glasses. The patient stands on a platform, which can be controlled as part of the virtual environment or as a reaction to movements of the patient. The patient wears optical or magnetic markers of which the position and orientation are recorded. These are fed into an algorithm that turns them into the degrees of freedom of the human body model, which is filled with the segment masses and inertia’s of the patient.

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Here is a selection of some relevent articles that used the CAREN system in its respective funcionalities. For Abstracts, refer to the press section on this site.

Kinematic response characteristics of the CAREN moving platform system for use in posture and balance research. Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Henry Cotton Campus, Webster Street, Liverpool L3 2ET, UK.
PMID: 16952478 [PubMed - in process]

Gait termination in lower limb amputees. Center for Rehabilitation, University Medical Center Groningen, University of Groningen, The Netherlands.
PMID: 17376689 [PubMed - as supplied by publisher]

A method for manipulating a movable platform's axes of rotation: a novel use of the CAREN system.
Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool L3 2ET, UK. G.J.Barton@livjm.ac.uk
PMID: 16464596 [PubMed - indexed for MEDLINE]

A treadmill and motion coupled virtual reality system for gait training post-stroke.
Jewish Rehabilitation Hospital (CRIR), McGill University, Montreal, Canada. joyce.fung@mcgill.ca
PMID: 16640470 [PubMed - indexed for MEDLINE]

Locomotor rehabilitation in a complex virtual environment.
Jewish Rehabilitation Hospital, McGill Univ., Montreal, Que., Canada.
PMID: 17271400 [PubMed - in process]

Reaching in reality and virtual reality: a comparison of movement kinematics in healthy subjects and in adults with hemiparesis.
Center for Interdisciplinary Research in Rehabilitation (CRIR), 6300 Darlington, Montreal, Quebec, Canada. mindy.levin@mcgill.ca.
PMID: 15679937 [PubMed - as supplied by publisher]

CAREN (computer assisted rehabilitation environment): a novel way to improve shoe efficacy.
Rehabilitation Center De Trappenberg, Huizen, The Netherlands.
PMID: 14571947 [PubMed - indexed for MEDLINE]

CAREN--Computer Assisted Rehabilitation Environment.
University of Amsterdam, Dept. of Rehabilitation, The Netherlands.
PMID: 10538390 [PubMed - indexed for MEDLINE]

CAREN helps patients to overcome balance disorders with Virtual Reality.
Virtual Medical Worlds Magazine, The Netherlands.
PMID: Published at HOISE.COM [www.hoise.com/vmw/articles/LV-VM-09-98-29]

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FUNDAMENTAL RESEARCH.Immersive VR that evaluates a subject's behavior and covers most sensory inputs (visual, auditory, vestibular, tactile) in a synchronized environment is a powerful research tool. The input and response of different senses can be isolated, compared, registered and evaluated at runtime or off-line. CAREN enables researchers to analyze balance behavior, latency, response times and the relations between different sensory inputs that affect human balance, posture and locomotion behaviors.

EARLY DIADNOSIS.CAREN is a quantifiable tool for early diagnosis of a variety of balance disorders, including Parkinson, Multiple Sclerosis and other degenerative conditions. It can detect tremors in a person attempting to stand still. An increase in this tremor over time often indicates the onset of a condition. Even a trained professional might not notice the anomalies early enough or distinguish a slight increase. Discovered early, these conditions can be treated more effectively. Doctors compare the data derived from the CAREN feedback loop of a specific patient, generating a quantitative diagnosis comparable with the motion data of a healthy people of the same age group and body proportions. Early diagnosis opens up the development of treatment not previously possible and can reduce long-term healthcare costs.

APPLIED REHABILITATION RESEARCH.One of CAREN’s big advantage is it's capability to give feedback on a patient's motion in real-time (< 0.04 sec!). This feedback cannot be reached today, using conventional therapeutic sessions, because a therapist is not fast enough to spot, register and give feedback to the patient. Much more, there are movements so slight, therapist can't perceive, because of human limitations, whereas CAREN can get, register and give feedback even the slightest movements performed by a patient. Thus, make the patient aware of his inefficient motion, and correct it while it occurs in the therapeutic session. A patient, who had suffered severe trauma to his foot, can be good example for CAREN's capabilities. The fact is that a big part of the rehabilitation process is overcoming the mental barrier (in this example, the anticipation of pain), which makes the patient hesitant to place all his weight on the injured leg. Using CAREN, the physicist can create a situation where the platform is raised slightly higher than the patient expects so he will step down sooner and apply, involuntarily, more pressure on the injured leg. In this way, the rehabilitation time, in some cases, can be shorten from about 3 months to about 3 weeks.

SPORTS AND SPORTS MEDICINE RESEARCH.Sports training is an intellectual process. A trainer evaluates the performance of an athlete and recommends improvements. The athlete interprets the trainer's input and trains towards achieving the targets set by the trainer. CAREN changes the training process from a cognitive process to a physical process by putting the athlete in a situation where he feels physically what the trainer means. For example, studies demonstrate that most long distance runners waste about 15-20 percent of their energy when running because of not achieving the most optimal forward vector. Redundant upward motion or bounce movement is the main cause. CAREN helps to train the athlete to eliminate this tendency. It captures the athlete’s movements on the system and intervenes by presenting the athlete an active ground that comes to meet the foot on the correct vector. The athlete feels physically what the optimal curve should be.

TRANSFER FOM VR TO DAILY LIFE ACTIVITIES.Virtual environments provide doctors with the means of almost unlimited exploratory behaviours and accurate measurement tools for evaluating progress in a rehabilitation process. Patients can visualize processes while standing still, amplifying one's balance awareness. They can experience specific situations or processes that in the user's perception require the need for correction of balance to reach a set target. They can experience every day life environments that need enhancing. Visualizations include standing on an escalator, navigating an airplane, catching a ball, walking a tight rope, shopping at a supermarket etc.

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CAREN's unique property is the ability to immerse a person in a multi-sensory experience. The person can for example see and hear how his balance compensation works. This allows for new insights in all disciplines relating to understanding our control and motor systems. CAREN creates a state which is not possible in nature. There is no situation in nature where a person is directly responsible for the motion of the ground he is standing on. This allows for unique observation of the adaptation process of our balance system to a new situation. There are no memories of such a condition thus the balance awareness of the person experiences a state similar to the learning state it was in when learning to stand or walk at an early age. In the 1st few seconds when the Feedback loop starts, we get a new understanding of our motor control and balance compensation strategies.

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CAREN comes in different configuration settings, CAREN-BASE CAREN-EXTENDED and CAREN-HIGHEND.
For detailed spacial requirements and drawings, refer to the product section on this site.

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Background knowledge in programming and/or 3D animation is not needed, but can be an advantage.
CAREN's control software (D-Flow) has a scalable modular graphic user interface that allows creating complex experiments without any former knowledge in computer programming and/or 3D animation (although knowledge in these two areas can be very helpful). In clinical rehabilitation settings usually the patient is accompanied by a therapist, and the operator is interfacing with them.

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MOTEK's labs in Amsterdam and Culenborg in The Netherlands are the best place to have hands on work with CAREN in a research settings. Our systems can run all current configurations available. In addition, demos are available in the following locations:

1 .Rijks University Groningen - Groningen, The Netherlands - CAREN in Clinical environment, using PRIMAS motion capture system and Bertex force plates.

2.Twente University - Enschede, The Netherlands - CAREN in Biomechanics Research environment, using VICON motion capture system and VTI Cyber Gloves.

3.IRDPQ - Quebec City, CANADA - CAREN in a Gait lab and rehabilitation research Environment, using Optotrak motion capture system, Pohemous Magnetic system, Amti force plates and Xl50 HMD.

4.JRH - Montreal, CANADA - CAREN in a Medical research environment, using Vicon motion capture system, Custom platform and Amti force plates.

5.SHEBA Tel Aviv ISRAEL - CAREN in a full clinical setting at the Orthopedic rehabilitation hospital, using a 12 camera Vicon system, 2 AMTI forceplates, EMG, and large stereoscopic display screen.

For planning demos please contact MOTEK MEDICAL B.V (info@motekmedical.com)

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Yes, you can.

Elements like motion capture systems and/or other analogue input devices
(Force plates, EMG, EEG and so on) can be easily integrated into CAREN.
Currently, CAREN is compatible with VICON, PRIMAS and OPTOTRAK optical motion capture systems, POLHEMOUS and ASCENSION electro-magnetic motion capture systems, VTI Cyber Gloves fingers motion capture system and Bertex , AMTI and TMS (Twente Medical Systems) Analogue input systems.
Furthermore, CAREN's SDK enables to easily program new modules and link many I/O devices.

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CAREN software is generating output file formats that can be read directly into MATLAB, SPSS and various other data analysis software packages. 3D databases created for CAREN are compatible with Softimage3D, XSI, Maya and a range of other 3D tools. The output format of CAREN can also be easily modified to fit client's specific requirements.

That depends on the chosen configuration CAREN-BASE has a lead-time of 6-8 weeks from order placement to delivery. Installation time may take a week, assuming that the hall (where the motion platform will be placed) and other constructions needed are installation ready. CAREN HighEnd system delivery time can be up to 20 weeks, mainly needed for building the dome projection system, the instrumented treadmill and some of the other components