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Pedestrian navigation based on a waist-worn inertial sensor.

Alvarez JC, Alvarez D, López A, González RC - Sensors (Basel) (2012)

Bottom Line: We present a waist-worn personal navigation system based on inertial measurement units.The device makes use of the human bipedal pattern to reduce position errors.We describe improved algorithms, based on detailed description of the heel strike biomechanics and its translation to accelerations of the body waist to estimate the periods of zero velocity, the step length, and the heading estimation.

View Article: PubMed Central - PubMed

Affiliation: Multisensor Systems & Robotics Lab (SiMuR), Department of Electrical and Computer Engineering, University of Oviedo, Campus de Gijón, Edificio n°2, Gijón 33204, Spain. juan@uniovi.es

ABSTRACT
We present a waist-worn personal navigation system based on inertial measurement units. The device makes use of the human bipedal pattern to reduce position errors. We describe improved algorithms, based on detailed description of the heel strike biomechanics and its translation to accelerations of the body waist to estimate the periods of zero velocity, the step length, and the heading estimation. The experimental results show that we are able to support pedestrian navigation with the high-resolution positioning required for most applications.

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Location C for large-range indoor experiments, 179 m length with 540 degrees turns. (a) Partial shorter experiments within the same environment, see Table 1; (b) Real-time path reconstruction.
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f3-sensors-12-10536: Location C for large-range indoor experiments, 179 m length with 540 degrees turns. (a) Partial shorter experiments within the same environment, see Table 1; (b) Real-time path reconstruction.

Mentions: The approach we take to overcome this limitation has two parts. First, we implement a basic algorithm to distinguish whether the individual is moving in a straight line or is turning, in order to disable the gyro integration to avoid unnecessary error accumulation. We assume that rotation speed around the vertical axis (Z axis) has two components, an AC component with the same frequency as the stride, which accounts for trunk rotation during normal gait, and a lower frequency component associated to the orientation change rate. Under this assumption, the absolute value of the mean of the Z component of rotation speed over a stride (MRZ) should be close to zero for straight walking and greater than zero for curved walking. Taking the absolute value allows to get rid of rotation direction. Figure 2 shows the distribution of MRZ for walk experiments in location of Figure 3(a).


Pedestrian navigation based on a waist-worn inertial sensor.

Alvarez JC, Alvarez D, López A, González RC - Sensors (Basel) (2012)

Location C for large-range indoor experiments, 179 m length with 540 degrees turns. (a) Partial shorter experiments within the same environment, see Table 1; (b) Real-time path reconstruction.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472842&req=5

f3-sensors-12-10536: Location C for large-range indoor experiments, 179 m length with 540 degrees turns. (a) Partial shorter experiments within the same environment, see Table 1; (b) Real-time path reconstruction.
Mentions: The approach we take to overcome this limitation has two parts. First, we implement a basic algorithm to distinguish whether the individual is moving in a straight line or is turning, in order to disable the gyro integration to avoid unnecessary error accumulation. We assume that rotation speed around the vertical axis (Z axis) has two components, an AC component with the same frequency as the stride, which accounts for trunk rotation during normal gait, and a lower frequency component associated to the orientation change rate. Under this assumption, the absolute value of the mean of the Z component of rotation speed over a stride (MRZ) should be close to zero for straight walking and greater than zero for curved walking. Taking the absolute value allows to get rid of rotation direction. Figure 2 shows the distribution of MRZ for walk experiments in location of Figure 3(a).

Bottom Line: We present a waist-worn personal navigation system based on inertial measurement units.The device makes use of the human bipedal pattern to reduce position errors.We describe improved algorithms, based on detailed description of the heel strike biomechanics and its translation to accelerations of the body waist to estimate the periods of zero velocity, the step length, and the heading estimation.

View Article: PubMed Central - PubMed

Affiliation: Multisensor Systems & Robotics Lab (SiMuR), Department of Electrical and Computer Engineering, University of Oviedo, Campus de Gijón, Edificio n°2, Gijón 33204, Spain. juan@uniovi.es

ABSTRACT
We present a waist-worn personal navigation system based on inertial measurement units. The device makes use of the human bipedal pattern to reduce position errors. We describe improved algorithms, based on detailed description of the heel strike biomechanics and its translation to accelerations of the body waist to estimate the periods of zero velocity, the step length, and the heading estimation. The experimental results show that we are able to support pedestrian navigation with the high-resolution positioning required for most applications.

Show MeSH