One or two Kinarm Exoskeleton robots for the upper limbs
Kinarm Exoskeleton Lab uses a complex linkage to permit planar movements of the arm in the horizontal plane involving flexion and extension movements at the shoulder and elbow joints. The Lab was extensively redesigned in 2016 to enhance stiffness and enable full access to the head for TMS, and other neuro-stimulation techniques.
Torque motors record the motion of the arm in the horizontal plane and apply loads to each joint independently. The design provides feedback from, and control of, the shoulder and elbow joints thus permitting loads to be applied to the shoulder and/or elbow joints (or hand-based loads). Patterns of joint motion are recorded; muscular torques are computed by the system.
Each Kinarm robot can be used as an exoskeleton for the shoulder and elbow (leaving the hand free to interact with objects in the environment) or converted to a hand-based end-point robot with an open handle.
The use of two Kinarm robots enables comparison of inter-arm performance as well as the study of bimanual coordination.
The application of loads directly to the upper arm and forearm is unique and resulted in issued US, Canadian and European Patents. (U.S. Patent No. 6,155,993; 8,347,710 & 8,800,366; Canadian Patent No. 2,267,821; EP No. 2,150,175).
2D virtual/augmented reality display
A virtual-reality system permits control over visual stimuli and even vision of the limb.
Dexterit-E™ experimental control software and hardware
Each Lab includes Dexterit-E™ behavioural control and data acquisition software, which combines the power of a real-time operating system with the ease of a Windows™-based interface. Kinarm Standard Tests can be used to enable immediate data collection, analysis and reporting, without the need for programmers. (U.S. Patent No. 8,277,396, 8,740,794; CN Patent No. ZL200780047665.6; JP Patent No. 5368311; CA & EP Patent Applications pending). Custom Task Programs can be created using high-level graphical programming tools.
Integrated Gaze-Tracking (optional)
A head-free gaze-tracker solution that: simplifies experimental set-up, ensuring nothing interferes with the head which is especially important in clinical research; and is easily accommodated in the Kinarm Virtual Reality System where space is limited. Download tech sheet.
Kinarm Users benefit from an exponential increase in experimental possibilities, without the headache of having to customize and coordinate multiple hardware solutions.
Components of the Human Kinarm Exoskeleton Lab
- Two motorized Kinarm™ Exoskeleton robots for simultaneous right and left-handed investigation; unilateral robot optional
- Workstation and visual display for presentation of 2D virtual targets in the actual plane of limb motion
- System-integrated chair with wheelchair-style seating (including removable foot, arm and head rests)
- Dexterit-E data acquisition and experimental control software
- A library of Simulink® blocks to assist with rapid custom task program creation (MATLAB®, and Simulink® and other MathWorks’ toolboxes must be purchased separately)
- Control hardware to run Dexterit-E (including a real-time computer for precise and safe action)
- Data acquisition hardware, optionally including up to 32 channels of analog input, 4 channels of analog output and 30 channels of digital input/output.
- Kinarm Standard Tests™
- Kinarm Gaze-Tracker
- Child-size arm troughs
- Subject Harness, for clinical researchers working with stroke subjects to keep them in a comfortable posture
Robot & System Specifications
- Real-time control at 2 kHz and data acquisition at 1kHz
- Peak torque pulse of 16.5 Nm; 5.5 Nm continuous (~25% more than KINARM Classic)
- Feedback resolution of 0.0006° (~4 microns at the hand) (absolute encoders are now standard)
- Vertical out-of-plane stiffness of 8,500 N/m; end-point in-plane mechanical stiffness of 16,400 N/m (~2-3 times the KINARM Classic)
- ~3X higher gains for position control relative to KINARM Classic
- minimum 47″ visual display/workspace
- Fits children as young as 5 – 6 years old (with optional child-size arm troughs) and adults up to approximately 6’6″ (2 m)
- Minimum suggested lab size 10′ x 10′ (3 m x 3 m); 10’ x 12’ (3 m x 3.5 m) will provide additional comfort.
- Clinical researchers may wish to allow 14’ x 18’ (4.3 m x 5.5 m) to allow easy transfer of subjects in wheelchairs.
- Kinarm Gaze-Tracker Specification
- Sampling Rate: 500 Hz
- Subject Setup: requires a quick 13 point calibration
- Resolution: 0.05°RMS; saccade resolution of 0.25°.
- Recovery from Loss of Tracking: A target sticker on the subject’s head provides eye distance and relative position information for fast recovery when tracking is interrupted.
- Accuracy: With minimal head movement, BKIN has measured a mean accuracy under ~0.5° in the Kinarm Lab workspace. With extreme head motion, we have observed some correlated inaccuracy up to ~1°.
- Workspace Area: The range over which gaze-tracking is possible is roughly ellipsoid: ~55° in the horizontal and ~40° in the vertical. In the horizontal plane of the Kinarm Virtual Reality System, these gaze angle ranges correspond to ~50 cm x ~30 cm. This range does not cover the entire Virtual Reality workspace in a KINARM Lab, which is a much larger workspace. The gaze-tracker is centered in the middle of the Kinarm Lab workspace so that the range is optimized for use with the KINARM.
- Service/Warranty: BKIN provides full technical support on Kinarm Gaze-Trackers.
- Regrettably the KINARM Gaze-Tracker cannot be used independent of the Kinarm Lab due to customizations to fit the Kinarm’s unique arrangment.
Integration with Third-Party Systems
Kinarm Labs can interact with many other technologies. In all cases, the data from the external systems can be acquired by the Kinarm Lab in real-time to ensure that the data is synchronized both for post-experiment analysis, and for online use. Examples include: EMG, EEG, TMS – any technology that accepts digital or analog inputs/outputs. For example, see Torrecillos, et al, 2014 for publication that recorded EEG simultaneously with reaching movements in the Kinarm Exoskeleton.
The Kinarm Exoskeleton lab was invented by Stephen Scott of Queen’s University at Kingston (Kinesiological Instrument for Normal and Altered Reaching Movements; Scott, 1999). He needed the Kinarm to address a major stumbling block in his own research: to identify the nature of neural representation in primary motor cortex (MI) during a reaching movement. Today its use has expanded greatly to not only be essential instrumentation to researchers studying sensorimotor control in NHP and human subjects, but also to researchers studying neurological dysfunction.
The Kinarm Exoskeleton Lab is particularly suitable for subjects with stroke, spinal cord injury or cerebral palsy as the Exoskeleton design provides gravity support of the subject’s upper limbs. Thus, even though a subject may have significant weakness in their arm(s), they may have sufficient motor function to attempt a behavioural task and provide an assessment. To properly fit the Exoskeleton to the subject, a 5-10 minute set-up by a trained technician is required.
Children as young as 5 and as old as 85 have been assessed in the Kinarm Exoskeleton Lab.
There are numerous published studies using the Kinarm Classic Exoskeleton Lab in clinical research. These include:
Fetal Alcohol Syndrome