D2.1 Requirements and Specification - CORBYS

D2.1 Requirements and Specification
10.2.4 Environmental sensing
Beyond the human-robot interface, the CORBYS gait rehabilitation system will not need extensive system
environment sensing. The main needs are related to the need for collision avoidance and for ensuring a safety
zone for the system users. This would most likely be accomplished by using a simple optical (laser beam) or
mechanical switching systems to prevent the system from having collisions or from falling down a stair.
10.2.5 Physiological multi sensor devices
Several combined sensor systems measuring multiple parameters exist. Also validated chest belts sending
heart rate data via a documented Bluetooth protocol are commercially available e.g. Hidalgo Equivital
system 14 , as shown in Figure 24. This systems measures heart rate, respiratory rate, chest skin temperature,
activity, posture and also has a fall detection algorithm as well as a Physiological Welfare Indication based on
heart rate and respiratory rate.
Figure 24: Hidalgo Equivital measuring unit (left) and belt (right)
SINTEF has also developed a sensor belt sending data over Bluetooth to a cell phone (which in turn sends
data to a server so that a nurse may follow the patient). The system is to be tested in home monitoring of
patients with congestive heart failure in the US autumn 2011. The chest unit is shown in Figure 25, and
includes simple ECG (heart rate), 3D accelerometer, 3D gyroscope and IR skin temperature sensor.
Figure 25: SINTEF ESUMS chest unit belt
10.3 Interpretation of multiple sensor signals
The development of sensor fusion algorithms has for several years been viewed as an important perceptual
activity in mobile robotics [Murphy, 1996]. Sensor fusion is a term used to describe how multiple
independent sensors are combined to extract and refine information not available through single sensors alone.
14 www.equivital.co.uk
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