定位相关论文-A Novel Pedestrian Dead Reckoning Algorithm for Multi-Mode Recognition Based on Smartphones
這里寫目錄標題
- 0.Abstract:
- 0.1逐句翻譯
- 0.2總結
- 1. Introduction
- 1.1逐句翻譯
- 第一段(當前的定位應用很發達,但是室內定位是一個缺口)
- 第二段(當前的主要方式-基于指紋類的)
- 第三段(這里介紹行人航跡推算的內容,會隨著時間變飄,有比較好的算法,但是那個是綁在腳上的)
- 第四段(介紹其他的人的個鐘頭方式,這些方式都多少還有些問題)
- 第五段(PDR的一個關鍵是航向,有些論文提出使用卡爾曼濾波來進行修正)
- 第六段(介紹本文提出的新方法)
- 第七段(介紹本文接下來寫的什么東西)
- 1.2總結
- 2. Materials and Methods
- 2.1. Proposed System Scheme(提出的解決方案)
- 2.1.1逐句翻譯
- 第一段(介紹傳統的PDR和本文的坐標系規定)
- 第二部分(介紹傳統方法的航向、位置、速度獲得的方法)
- 第三段(簡單介紹本文的方法)
- 2.1.2總結
- 2.2. Step Detection Based On State Transition
- 第一部分(敘述怎么處理數據的)
- 第二部分(具體描述怎么進行狀態轉化的)
- 第三部分
0.Abstract:
0.1逐句翻譯
With the rapid development of smartphone technology, pedestrian navigation based on built-in inertial sensors in smartphones shows great application prospects.
隨著智能手機技術的快速發展,基于智能手機內置慣性傳感器的行人導航顯示出了巨大的應用前景。(用手機的多了,用手機定位的場景自然就多了)
Currently, most smartphone-based pedestrian dead reckoning (PDR) algorithms normally require a user to hold the phone in a fixed mode and, thus, need to correct the gyroscope heading with inputs from other sensors, which restricts the viability of pedestrian navigation significantly.
目前,大多數基于智能手機的行人航位推算(PDR)算法通常要求用戶手持手機處于固定模式,因此需要使用其他傳感器的輸入來修正陀螺儀的航向,這極大地限制了行人導航的可行性。
In this paper, in order to improve the accuracy of the traditional step detection and step length estimation method for different users, a state transition-based step detection method and a step length estimation method using a neural network are proposed.
為了提高傳統的步長檢測和步長估計方法對不同用戶的精度,提出了一種基于狀態轉移的步長檢測方法和一種基于神經網絡的步長估計方法。
In order to decrease the heading errors and inertial sensor errors in multi-mode system, a multi-mode intelligent recognition method based on a neural network was constructed.
為了減小多模態系統的航向誤差和慣性傳感器誤差,提出了一種基于神經網絡的多模態智能識別方法。
(這個文章使用神經網絡識別了一種持有姿態)
On this basis, we propose a heading correction method based on zero angular velocity and an overall correction method based on lateral velocity limitation (LV).
在此基礎上,提出了一種基于零角速度的航向校正方法和一種基于橫向速度限制(LV)的整體校正方法。
Experimental results show that the maximum positioning errors obtained by the proposed algorithm are about 0.9% of the total path length.
實驗結果表明,該算法獲得的最大定位誤差約為總路徑長度的0.9%。
The proposed novel PDR algorithm dramatically enhances the user experience and, thus, has high value in real applications.
該算法顯著提高了用戶體驗,具有較高的實際應用價值。
0.2總結
大約就是提出了下面的組成部分:
- 1.提出了一種狀態機的步長估計和一種神經網絡的步長估計
- 2.一種基于神經網絡的持有姿態識別
- 3.一種基于角度限制的航向修正。
然后取得了很好的效果
1. Introduction
1.1逐句翻譯
第一段(當前的定位應用很發達,但是室內定位是一個缺口)
With the development of society, location-based service became part of people’s lives.
隨著社會的發展,基于位置的服務成為人們生活的一部分。
A pedestrian navigation and positioning service system mainly depends on a global positioning system (GPS) in an outdoor environment [1,2].
行人導航定位服務系統主要依賴于室外環境下的全球定位系統(GPS)[1,2]。(就是室外可以使用GPS,但是室內就沒有這個東西了)
For indoor applications in, e.g., airports, train stations, underground garages, and shopping malls, GPS often becomes unavailable because of signal occlusion, which would hinder the application of location-based services in these areas.
對于機場、火車站、地下車庫、商場等室內應用,GPS常常因為信號遮擋而無法使用,這將阻礙基于位置的服務在這些區域的應用。
Therefore, pedestrian indoor navigation technology is critical to ensure the success of location-based services.
因此,行人室內導航技術是確保位置服務成功的關鍵。
第二段(當前的主要方式-基于指紋類的)
Currently, pedestrian indoor navigation and positioning can be achieved using two types of methods.
The first type of method is based on wireless technologies, e.g., WiFi [3–5], ultra-wideband (UWB) [6,7], visual sensors [8], radio frequency identification (RFID) [9], ibeacon [10], Bluetooth, and/or ZigBee, with a multi-source information fusion technique [11] to obtain pedestrian location information.
第一種方法是基于無線技術,如WiFi[3-5]、超寬帶(UWB)[6,7]、視覺傳感器[8]、射頻識別(RFID)[9]、ibeacon[10]、藍牙和/或ZigBee等,采用多源信息融合技術[11]獲取行人位置信息。
(這些大約就是指紋類的方法來完成這個任務)
For the first type of method, its location errors do not accumulate over time. However, these methods need a significant cost to deploy wireless devices as beacons before navigation and are infeasible for the unknown environment.
對于第一種方法,它的定位誤差不會隨時間累積。然而,這些方法需要在導航前部署無線設備作為信標,并且在未知環境下是不可行的。
(這個東西是比較準的就是關鍵是得提前部署這些東西,一定程度上限制了使用)
第三段(這里介紹行人航跡推算的內容,會隨著時間變飄,有比較好的算法,但是那個是綁在腳上的)
In these methods, an inertial sensor is fixed on the foot [13,14], waist [15,16], leg, or shoulder of a user for data acquisition, in order to determine the position of pedestrian using the number and the size of walking steps and the heading angle [17].
在這些方法中,將慣性傳感器固定在用戶的腳[13,14]、腰[15,16]、腿或肩膀上進行數據采集,利用行人行走的步數、步數大小和行走的方向角[17]來確定行人的位置。
These methods belong to autonomous positioning technologies and have a high positioning accuracy in a short-time period.
這些方法屬于自主定位技術,在短時間內具有較高的定位精度。
(推久了就開始飄了)
However, their positioning performance is drastically affected by the accumulative errors of iterative calculation.
但其定位性能受迭代計算的累積誤差影響較大。
Therefore, many researchers are committed to solving the accumulative errors in the traditional PDR algorithm [18,19].
因此,許多研究者致力于解決傳統PDR算法中的累積誤差問題[18,19]。
Zhou et al. [19] proposed a PDR algorithm with low computational complexity using a foot-mounted inertial measurement unit (IMU) and estimating orientation of the foot based on extended Kalman filter (EKF), which can correct the accumulative errors of PDR.
Zhou et al.[19]提出了一種計算復雜度較低的PDR算法,該算法利用足部慣性測量單元(IMU)和基于擴展卡爾曼濾波(EKF)的足部方位估計,可以修正PDR的累積誤差。
Nonetheless, it can only be applied for foot-mounted navigation and, therefore, has poor viability for different users.
然而,它只能應用于腳踏導航,因此,對于不同的用戶來說,可行性很差。(但是這種比較準的算法是綁在腳上的)
第四段(介紹其他的人的個鐘頭方式,這些方式都多少還有些問題)
The MEMS-based algorithm brings inconvenience to practical application due to the extrainstallation of inertial sensors.
MEMS-based的算法由于慣性傳感器的額外安裝給實際應用帶來了不便。
In allusion to the inconvenience of pedestrian positioning technology based on fixed inertial sensors, smartphone-based pedestrian navigation gradually became a research hotspot for experts.
針對基于固定慣性傳感器的行人定位技術帶來的不便,基于智能手機的行人導航逐漸成為專家們的研究熱點。
Bilke et al. [20] proposed a locating system based on recognizing geomagnetic field disturbances and ambient light.
Bilke et al.[20]提出了一種基于地磁場擾動和環境光識別的定位系統。
Li [21] combined Bluetooth and an inertial navigation system to implement a set of navigation systems based on a smartphone.
Li[21]結合藍牙和慣性導航系統,實現了一套基于智能手機的導航系統。
Kang and Han [22] designed a smartphone-based algorithm, named smartPDR, but users had to reduce the sway of the smartphone in experiments.
Kang和Han[22]設計了一種基于智能手機的算法,名為smartPDR,但在實驗中,用戶必須減少智能手機的搖擺。
Wang et al. [23] presented a PDR approach based on motion mode recognition using a smartphone.
Wang et al.[23]提出了一種基于智能手機運動模式識別的PDR方法。
The motion mode recognition was achieved using a support vector machine (SVM) and a decision tree (DT), which thereby increased the complexity of the algorithm.
運動模式識別采用支持向量機(SVM)和決策樹(DT)實現,增加了算法的復雜性。(如果增加運動模式識別,至少需要使用到某種機器學習模型,所以復雜度會有所上升)
Zeng et al. [24] proposed an autonomous inertial heading correction algorithm based on the Kalman filter and the different usage modes of the smartphone, e.g., normal mode, landscape mode, or call mode.
Zeng等人[24]提出了一種基于卡爾曼濾波的自主慣性航向校正算法,該算法結合智能手機的不同使用模式,如正常模式、橫向模式、通話模式。
(大約就是用卡爾曼濾波進行誤差修正)
The usage mode could be determined based on the gravity-assisted (GA) method. However, in References [22–24], step detection methods were both based on peak detection, which would introduce detection errors due to the step detection errors.
利用重力輔助(GA)方法可以確定使用模式。但是在文獻[22-24]中,階躍檢測方法都是基于峰值檢測的,由于階躍檢測誤差會引入檢測誤差。
Moreover, the step length estimation method was based on a nonlinear model or constant which would cause position errors for different users.
此外,步長估計方法是基于非線性模型或常數,對不同的用戶會產生位置誤差。
Furthermore, mode recognition methods do not have universality, as the accuracy of these methods is affected by the configurations of the threshold.
此外,模式識別方法不具有通用性,因為這些方法的準確性受到閾值配置的影響。
第五段(PDR的一個關鍵是航向,有些論文提出使用卡爾曼濾波來進行修正)
The heading error is the one of the main error sources in PDR.
航向誤差是PDR的主要誤差來源之一。
In References [20–22], smartphone-based navigation algorithms required users to hold a smartphone in a fixed mode as long as possible.
在文獻[20-22]中,基于智能手機的導航算法要求用戶盡可能長時間地保持智能手機的固定模式。
(PDR的一個關鍵就是獲得一個準確的航向,所以這就要求大家使用一個固定的狀態拿著手機,來獲得一個準確的航向)
However, it is difficult for users to keep a fixed mode during the movement process, which leads to significant heading errors.
但在移動過程中,用戶難以保持固定的模式,導致了較大的航向誤差。
Wang et al. [23] proposed a principal component analysis (PCA)-based method with global accelerations (PCA-GA) to infer pedestrian headings.
Wang et al.[23]提出了一種基于主成分分析(PCA)的全局加速度(PCA- ga)方法來推斷行人標題。
However, one set of experiments represented only one phone pose, which is not applicable to multi-mode changes of a smartphone.
然而,有一組實驗只代表了一種手機姿勢,這并不適用于智能手機的多模式變化。
Although Reference [24] proposed using a Kalman filter to correct the heading errors in a multi-mode application, heading correction values are hard to estimate precisely due to weak constraints and observation
errors.
雖然參考文獻[24]提出在多模式應用中使用卡爾曼濾波器來校正航向誤差,但由于約束條件和觀測誤差較弱,難以精確估計航向修正值。
第六段(介紹本文提出的新方法)
In this paper, we propose a novel pedestrian dead reckoning algorithm for multi-mode recognition based on a smartphone.
本文提出了一種基于智能手機的行人航跡推算多模式識別算法。
Firstly, different from the peak detection in References [22–24], state transition was carried out to improve the accuracy of step detection for different phone modes.
首先,與文獻[22-24]中的峰值檢測方法不同的是,為了提高對不同電話模式的計步器的準確性,我們進行了狀態轉移。
(為了提升不同手機姿態下步伐檢測的準確性本文提出了一種狀態轉移的計步器)
Secondly, we adopted the neural network to obtain the step length and the smartphone mode without setting thresholds manually, which increased the universality of step length estimation and mode recognition methods.
其次,在不手動設置閾值的情況下,采用神經網絡獲取步長和智能手機模式,提高了步長估計和模式識別方法的通用性;
The main contributions of the paper are that we design the heading correction method based on zero angular velocity (ZA) and an overall correction method based on lateral velocity limitation (LV) to correct the error of heading estimation and inertial sensors in a smartphone-based PDR.
本文的主要貢獻在于設計了基于零角速度(ZA)的航向修正方法和基于橫向速度限制(LV)的整體航向修正方法,對基于智能手機的PDR中的航向估計和慣性傳感器的誤差進行了修正。
Experimental results show that the algorithm proposed in this paper is effective.
實驗結果表明,本文提出的算法是有效的。
第七段(介紹本文接下來寫的什么東西)
The rest of the paper is organized as follows:
Section 2 presents our proposed algorithm in detail, including the comparison between the traditional PDR algorithm and the proposed novel PDR algorithm, along with the step detection, step length estimation, multi-mode intelligent recognition,and heading correction methods.
第2節詳細介紹了我們提出的算法,包括傳統PDR算法和新PDR算法的比較,以及步長檢測、步長估計、多模式智能識別和航向校正方法。
The experimental results are systematically analyzed in Section 3.
實驗結果將在第三部分進行系統分析。
Sections 4 and 5 discuss the system and draw conclusions.
第4節和第5節討論了系統并得出結論。
1.2總結
這里大約介紹了:
- 1.隨著社會發展定位的應用越來越廣泛,但是室內定位仍然存在問題。
- 2.室內定位存在兩種方法一種是指紋的方法,一種是行人航跡推算的方法
- 3.之前比較準的算法是綁在腳上的,這個綁在腳上限制了應用。
- 4.介紹其他人的具體方法,反正就是都有不足。
- 5.航向的誤差也是一個急需解決的問題。
- 6.本文使用的方法。
別管怎樣這里大約就是說了之前的兩個問題:
- 1.手機的持有狀態是不一樣的,所以需要采用多種不同的方式來處理
這里的處理其實包括兩方面:1)怎么識別這些狀態 2)怎么應對這些狀態。 - 2.隨著時間傳感器推算會逐漸變得不準確。
所以本文提出了一個方法:
- 1.首先使用神經網絡獲得一個持有姿態。
- 2.之后根據不同的持有姿態獲得不同的計步器和步伐檢測。
- 3.之后使用零角度速度和時序上長時間的速度限制,修正長時間的傳感器漂移
2. Materials and Methods
2.1. Proposed System Scheme(提出的解決方案)
2.1.1逐句翻譯
第一段(介紹傳統的PDR和本文的坐標系規定)
As shown in Figure 1, using an accelerometer and a gyroscope, the traditional scheme of the PDR algorithm estimates the position, velocity, and heading using the results of step detection, step length estimation, and heading estimation.
如圖1所示,PDR算法的傳統方案使用加速度計和陀螺儀,利用階躍檢測、步長估計和航向估計的結果估計位置、速度和航向。
(大約就是介紹一下之前的PDR都是怎么做的)
In Figure 1, f and ω are the outputs of the accelerometer and gyroscope, respectively, flag indicates the result of step detection, L is the step length estimation, and φ is the heading estimation of the pedestrian.
譯文:在圖1中,f和ω分別為加速度計和陀螺儀的輸出,flag為步長檢測結果,L為步長估計,φ為行人的航向估計。
e result of step detection, L is the step length estimation, and Ф is the heading estimation
行人導航涉及人體坐標系和導航坐標系。
The x-axis of the body coordinate system corresponds to the lateral direction of the smartphone, the y-axis corresponds to the forward direction of the smartphone, and the z-axis satisfies the right-hand rule.
身體坐標系的x軸對應智能手機的橫向方向,y軸對應智能手機的正向方向,z軸滿足右手規則。(也就是右前上載體坐標系)
The navigation coordinate system involves east, north, up (ENU) coordinates.
導航坐標系為東北天。
第二部分(介紹傳統方法的航向、位置、速度獲得的方法)
The traditional heading estimation method uses a z-axis gyroscope ωzk, denoted by
傳統的航向估計方法采用z軸陀螺儀ωzk,表示為
where ?k and ?k?1 are the headings at time instants kT and (k ? 1)T, respectively. The initial heading is set manually.
其中?k和?k - 1分別是時刻kT和(k - 1)T的航向。初始航向是手動設置的。
(這里注意heading是定位當中航向的意思)
大致想一下就是這里使用z軸的陀螺儀數據是可以用來判定航向的變化的,以此來推算當前航向的變化。(但是這個東西一切都是建立在手機是平端的情況下的)
The traditional position estimation method is resolved using the step length Li and the heading of the i-th step, denoted by
傳統的位置估計方法是用步長Li和第i步的方向來解決的,用
也就是使用方向加上步長得到移動的距離
The velocity estimation method is calculated by
速度估計方法是由
where T represents sampling period, fx,k and fy,k are the lateral acceleration and forward acceleration on the horizontal plane at time instants kT, and fe,k and fn,k are the eastward acceleration and northward acceleration at time instants kT.
式中,T為采樣周期,fx、k、fy,k為時刻kT水平面上的橫向加速度和正向加速度,fe、k、fn、k為時刻kT的東向加速度和北向加速度。
Then, the eastward velocity and northward velocity are calculated by
(大約就是我們通過載體坐標系加上航向角,其實就是姿態角可以解算出北向和東向的加速度,可以分別的獲得北向和東向的速度,這里其實當前這個公式有個什么問題呢就是這個公式當中默認加速度是不變的。所以這就存在誤差。)
第三段(簡單介紹本文的方法)
The accurate estimations of step, step length, and heading are crucial for a pedestrian navigation algorithm.
準確估計步數、步長和方向是行人導航算法的關鍵。
Since the accuracy of built-in inertial sensors in a smartphone is at a lower level,the traditional PDR algorithm would have relatively large navigation errors; in particular, the drift of heading can result in a drastic increase in errors.
由于智能手機內置慣性傳感器的精度較低,傳統的PDR算法存在較大的導航誤差;特別是,艏向的漂移會導致誤差的急劇增加。
In addition, considering the user experience, this paper studies a multi-mode smartphone-based navigation algorithm.
此外,考慮到用戶體驗,本文研究了一種基于智能手機的多模式導航算法。
In order to solve the defects of the traditional PDR algorithm, we propose a novel PDR algorithm, which includes step detection based on state transition, a step length estimation method based on neural network and differential GPS, and multi-mode intelligent recognition, a heading correction method based on zero angular velocity (ZA), and an overall correction method based on lateral velocity limitation (LV), as shown in Figure 2.
為了解決傳統的PDR算法的缺陷,我們提出一種新穎的PDR算法,包括基于狀態轉換步驟檢測,步長估算方法基于神經網絡和差分GPS和多模智能識別,基于零角速度的航向修正方法(ZA),以及基于橫向速度限制(LV)的整體校正方法,如圖2。
In the figure, the purple dotted boxes represent the neural networks which are outlined by different features. We estimate the results directly using these neural networks in a PDR algorithm.
在圖中,紫色虛線框表示由不同特征勾勒出的神經網絡。我們在PDR算法中直接使用這些神經網絡來估計結果。
2.1.2總結
首先,介紹傳統方法:
首先大致介紹傳統PDR的情況,也同時說明了本文的載體(手機)坐標系為右前上,導航坐標系為東北天。當然本文作者描述坐標系的方法是使用傳統上都這么做的方法,但是其實還有前右下和北東地。
之后,詳細介紹傳統方法獲得位置航向速度的方法。
最后,簡單展示了本文獲得這三個信息的方式。
2.2. Step Detection Based On State Transition
第一部分(敘述怎么處理數據的)
During the walking process of the human handheld smartphone, the lifting and undulating of the foot cause the lifting and undulating of the human body. This cyclical fluctuation is reflected in the acceleration of the smartphone, as shown in Figure 3a.
在人類手持智能手機行走過程中,足部的抬升和波動會引起人體的抬升和波動。這種周期性波動反映在智能手機的加速上,如圖3a所示
The delt-accNorm in Figure 3a represents the differences between the acceleration modulus and the modulus of the pedestrian’s initial stationary stage, denoted by Equation (5).
圖3a中的delt-accNorm表示加速度模量與行人初始靜止階段模量的差值,用式(5)表示。
(這里注意這個東西不是直接使用一個加速度模值,而是使用一個和靜止比較的模值)
The purpose of the differences is to reduce the difference of the threshold of step detection between different pedestrians.
差異的目的是減小不同行人的計步器檢測閾值的差異。
(他這里的意思是減少每個人在走路時候的差異,但是我個人覺得這里不能減少每個人的差異,例如每個人抬高的高度是不一樣的,就算使用這種方式也是不能解決的。但是這樣做確實可以消除每個人的在相同持有狀態分類下的習慣差異,例如每個人的平端可能多多少少有所不同)
In view of the noise of the accelerometer in the course of motion, the curve burr as shown in Figure 3a will reduce the accuracy of step detection.
由于加速度計在運動過程中存在噪聲,如圖3a所示的曲線毛刺會降低步進檢測的精度。
Thus, we smooth out the interference of acceleration using a moving average filter shown in Equation (6).
因此,我們使用式(6)中所示的移動平均濾波器消除加速度的干擾。
大約就是在一個窗口內取一個均值
The smoothed result is shown in Figure 3b.
平滑后的結果如圖3b所示
The valley value f_valley and the peak value f_peak of delt-accNorm are taken as the conditions of step detection.
以delta - accnorm的谷值f_valley和峰值f_peak作為步進檢測的條件。
(就是用波峰和波谷來進行檢測)
第二部分(具體描述怎么進行狀態轉化的)
The specific models are as follows:
具體模型如下:
(1) Peak value detection: if fk,peak > THpeak, then the mode-flag is set to 1.
(1)峰值檢測:如果fk,峰值>峰值THpeak,則mode-flag設置為1。
(這里就是超過一個閾值就把他當成一個波峰了)
(2) Valley value detection: if fk,valley > THvalley, and the time difference between the last peak and the valley value ?Tk,peak,valley satisfies ?Tk,peak,valley > THpeak,valley, then the mode-flag is set to 2.
大約就是說,這里的波谷不僅僅得小于閾值,還得和之前的波峰和波谷有一定的距離
(3) On the basis of (2), the next peak detection is carried out, and if the time difference between the last valley and this peak value (?Tk,valley,peak) satisfies (?Tk,valley,peak) > (THvalley,peak), then the mode-flag is set to 3.
我們再次檢查到波峰的時候我們也得和之前的波谷進行判斷。
(4) When the mode-flag is 3, it represents that we detected one step successfully. Then, the mode-flag is set to 1 and the cycle is repeated.
當mode-flag為3時,表示我們成功檢測到一個步驟。然后,將mode-flag設置為1,并重復此循環。
THpeak, THvalley, THpeak,valley, and THvalley,peak are the detection thresholds of peak value, valley value, the time difference between the last peak and the current valley value, and the time difference between the last valley and the current peak value, respectively.
THpeak、THvalley、THpeak、THvalley、THvalley、peak分別為峰值、谷值、最后一個峰值與當前谷值的時間差、最后一個峰值與當前峰值的時間差的檢測閾值。
The process of step detection is shown in Figure 4
步進檢測的過程如圖4所示
第三部分
The difference between the handheld and the foot-fixed smartphone-based navigation algorithm is that the latter has an obvious zero velocity interval [13], while the former has only very short zero velocity moments.
基于手持和基于腳的智能手機導航算法的不同之處在于,后者具有明顯的零速度區間[13],而前者只有非常短的零速度時間段。
The zero velocity moment of the handheld smartphone-based navigation is the first sampling period which is less than the modulus value of the initial stationary stage after the peak appears.
基于手持智能手機的導航的零速度時間段是第一個采樣周期小于峰值出現后初始穩定階段的模值。
Meanwhile, the zero velocity flag is set to 1. Moreover, in order to reduce the cumulative errors of velocity, the velocity of that moment is set to zero.
同時,將零速度標志設置為1。為了減小速度的累積誤差,將該時刻的速度設為零。
總結
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