Robust iterated extended Kalman filter algorithm for foot-mounted inertial measurement units/ultrawideband fusion positioning

Integrated UWB/MIMU Sensor System for Position Estimation towards an Accurate Analysis of Human Movement: A Technical Review

“…The PlusOn 410 UWB [ 34 ], UWB Mini4sPlus [ 54 ], and BeSpoon [ 43 ] were each used in one article. Twelve articles did not report on the UWB sensor that was used in their study [ 37 , 40 , 42 , 45 , 48 , 49 , 52 , 53 , 55 , 56 , 63 , 64 ]. Detailed information on the sensor systems used, along with their update rates, is provided in Table 1 .…”

“…Among the reviewed articles, the number of fixed anchors ranged from 1–10, where the majority of the articles (32 articles) used 3–5 anchors. Two of the articles used seven anchors [ 53 ] and ten anchors [ 40 ], respectively. Both the articles that used more than five anchors, stated that an increase in the number of anchors creates redundancy in the number of ranging, thereby increasing the robustness against situations of NLOS between one or more node pairs.…”

“…A wide range of MIMUs was used in the reviewed articles and the most commonly used MIMU sensor hardwares are Xsens IMU (Xsens BV, Enschede, Netherlands) [ 7 , 38 , 39 , 40 , 41 ], iPhone inbuilt IMU [ 47 , 50 , 57 , 58 , 67 ], and MPU9250/9150 (InvenSense Inc, San Jose, CA, USA) [ 31 , 33 , 44 , 53 , 63 ], which were each used in five articles. Custom-made MIMUs with individual sensors (accelerometer: ADXL203, gyroscope: ADXRS620, and magnetometer: HMC5983) [ 46 , 49 , 60 , 64 ] were used in four articles.…”

“…In the reviewed articles, the UWB and MIMU sensors on the body were not always integrated into a single sensor platform or placed physically tied to each other. The UWB and MIMU were placed at different locations on the body for 15 articles [ 31 , 32 , 37 , 39 , 42 , 44 , 45 , 46 , 48 , 49 , 53 , 55 , 56 , 60 , 64 ]. While for another 19 they were physically tied to each other and thus placed at the same location [ 7 , 33 , 34 , 35 , 38 , 40 , 41 , 43 , 47 , 50 , 54 , 57 , 58 , 59 , 61 , 62 , 63 , 65 , 67 ].…”

“…As previously mentioned in Section 3.2.1 , only one UWB tag was placed on the body and was placed mainly on the foot [ 33 , 34 , 40 , 54 , 61 , 63 , 65 ], on a shoulder backpack [ 45 , 46 , 48 , 49 , 55 , 56 , 60 , 64 ], or held in hand steady with no swinging [ 37 , 43 , 47 , 50 , 52 , 57 , 58 , 67 ]. Meanwhile, other articles had a placement on the waist [ 38 , 39 , 41 ], on a head-worn helmet [ 31 , 32 , 44 , 53 ], on the shoulder [ 42 , 59 ], or on the chest/trunk [ 62 ]. Zihajehzadeh et al 2017, [ 7 ] had three UWB sensors that were placed on the waist and both feet.…”