需求
設(shè)置飛機(jī)的一些坐標(biāo)位置(經(jīng)緯度高度)，插值得到更多的坐標(biāo)位置，然后飛機(jī)按照這些坐標(biāo)集合形成的航線飛行，飛機(jī)的朝向、俯仰角以及飛機(jī)轉(zhuǎn)彎時(shí)的翻轉(zhuǎn)角根據(jù)坐標(biāo)集合計(jì)算得出，而不需要手動(dòng)設(shè)置heading、pitch、roll。
坐標(biāo)插值
不知道為什么，可能是飛行速度變化太大，我用Cesium自帶的插值，計(jì)算出的航線很奇怪
// 如下代碼插值計(jì)算出的航線有問(wèn)題
property.setInterpolationOptions({
interpolationDegree : 5,
interpolationAlgorithm : Cesium.LagrangePolynomialApproximation
});
自己寫(xiě)的插值計(jì)算，效果等同于Cesium自帶的線性插值。
思路很簡(jiǎn)單，每次插值，就是取時(shí)間的中點(diǎn)，兩個(gè)坐標(biāo)的中點(diǎn)。
代碼如下：
/**
* 重新采樣this.DronePositions
*/
DetectsDrones.prototype.sameple = function () {
for (let i = 0; i < 3; i++) {
this.samepleOnce();
}
}
/**
* 重新采樣this.DronePositions
*/
DetectsDrones.prototype.samepleOnce = function () {
for (let i = 0; i < this.DronePositions.length - 1; i += 2) {
let pos1 = this.DronePositions[i];
let pos2 = this.DronePositions[i + 1];
let time1 = dayjs(pos1.time, 'YYYY-MM-DD HH:mm:ss');
let time2 = dayjs(pos2.time, 'YYYY-MM-DD HH:mm:ss');
let time = time1.add(time2.diff(time1) / 2.0, 'millisecond');
let lng = (pos1.targetPosition.lng + pos2.targetPosition.lng) / 2.0;
let lat = (pos1.targetPosition.lat + pos2.targetPosition.lat) / 2.0;
let height = (pos1.targetPosition.height + pos2.targetPosition.height) / 2.0;
let heading = (pos1.targetPosition.heading + pos2.targetPosition.heading) / 2.0;
let pitch = (pos1.targetPosition.pitch + pos2.targetPosition.pitch) / 2.0;
let roll = (pos1.targetPosition.roll + pos2.targetPosition.roll) / 2.0;
let pos = {
time: time.format('YYYY-MM-DD HH:mm:ss.SSS'),
targetPosition: {
lng: lng,
lat: lat,
height: height,
heading: heading,
pitch: pitch,
roll: roll,
}
}
this.DronePositions.splice(i + 1, 0, pos);
}
}
根據(jù)航線坐標(biāo)集合計(jì)算heading、pitch、roll
從網(wǎng)上抄的計(jì)算heading和pitch的方法(參考博客：https://blog.csdn.net/u010447508/article/details/105562542?_refluxos=a10)：
/**
* 根據(jù)兩個(gè)坐標(biāo)點(diǎn),獲取Heading(朝向)
* @param { Cesium.Cartesian3 } pointA
* @param { Cesium.Cartesian3 } pointB
* @returns
*/
function getHeading(pointA, pointB) {
//建立以點(diǎn)A為原點(diǎn)，X軸為east,Y軸為north,Z軸朝上的坐標(biāo)系
const transform = Cesium.Transforms.eastNorthUpToFixedFrame(pointA);
//向量AB
const positionvector = Cesium.Cartesian3.subtract(pointB, pointA, new Cesium.Cartesian3());
//因transform是將A為原點(diǎn)的eastNorthUp坐標(biāo)系中的點(diǎn)轉(zhuǎn)換到世界坐標(biāo)系的矩陣
//AB為世界坐標(biāo)中的向量
//因此將AB向量轉(zhuǎn)換為A原點(diǎn)坐標(biāo)系中的向量，需乘以transform的逆矩陣。
const vector = Cesium.Matrix4.multiplyByPointAsVector(
Cesium.Matrix4.inverse(transform, new Cesium.Matrix4()),
positionvector,
new Cesium.Cartesian3()
);
//歸一化
const direction = Cesium.Cartesian3.normalize(vector, new Cesium.Cartesian3());
//heading
let heading = Math.atan2(direction.y, direction.x) - Cesium.Math.PI_OVER_TWO;
heading = Cesium.Math.TWO_PI - Cesium.Math.zeroToTwoPi(heading);
return Cesium.Math.toDegrees(heading);
}
/**
* 根據(jù)兩個(gè)坐標(biāo)點(diǎn),獲取Pitch(仰角)
* @param { Cesium.Cartesian3 } pointA
* @param { Cesium.Cartesian3 } pointB
* @returns
*/
function getPitch(pointA, pointB) {
let transfrom = Cesium.Transforms.eastNorthUpToFixedFrame(pointA);
const vector = Cesium.Cartesian3.subtract(pointB, pointA, new Cesium.Cartesian3());
let direction = Cesium.Matrix4.multiplyByPointAsVector(Cesium.Matrix4.inverse(transfrom, transfrom), vector, vector);
Cesium.Cartesian3.normalize(direction, direction);
//因?yàn)閐irection已歸一化，斜邊長(zhǎng)度等于1，所以余弦函數(shù)等于direction.z
let pitch = Cesium.Math.PI_OVER_TWO - Cesium.Math.acosClamped(direction.z);
return Cesium.Math.toDegrees(pitch);
}
根據(jù)航線坐標(biāo)集合計(jì)算heading、pitch、roll：
代碼中this.DronePositions是無(wú)人機(jī)群的坐標(biāo)集合，坐標(biāo)放在targetPosition屬性中文章來(lái)源：http://www.zghlxwxcb.cn/news/detail-844251.html
/**
* 計(jì)算無(wú)人機(jī)群的heading
*/
DetectsDrones.prototype.calcHeading = function () {
// 清空原有heading
this.DronePositions.map(pos => {
pos.targetPosition.heading = undefined;
});
for (let i = 0; i < this.DronePositions.length - 1; i++) {
let pos1 = this.DronePositions[i];
let pos2 = this.DronePositions[i + 1];
let heading = -90 + getHeading(Cesium.Cartesian3.fromDegrees(pos1.targetPosition.lng, pos1.targetPosition.lat), Cesium.Cartesian3.fromDegrees(pos2.targetPosition.lng, pos2.targetPosition.lat));
if (!pos1.targetPosition.heading) {
pos1.targetPosition.heading = heading;
}
pos2.targetPosition.heading = heading;
}
}
/**
* 計(jì)算無(wú)人機(jī)群的pitch
*/
DetectsDrones.prototype.calcPitch = function () {
// 清空原有pitch
this.DronePositions.map(pos => {
pos.targetPosition.pitch = undefined;
});
for (let i = 0; i < this.DronePositions.length - 1; i++) {
let pos1 = this.DronePositions[i];
let pos2 = this.DronePositions[i + 1];
let pitch = getPitch(Cesium.Cartesian3.fromDegrees(pos1.targetPosition.lng, pos1.targetPosition.lat, pos1.targetPosition.height), Cesium.Cartesian3.fromDegrees(pos2.targetPosition.lng, pos2.targetPosition.lat, pos2.targetPosition.height));
if (!pos1.targetPosition.pitch) {
pos1.targetPosition.pitch = pitch;
}
pos2.targetPosition.pitch = pitch;
}
}
/**
* 計(jì)算無(wú)人機(jī)群的roll(不支持轉(zhuǎn)彎大于90度)
*/
DetectsDrones.prototype.calcRoll = function () {
// 清空原有roll
this.DronePositions.map(pos => {
pos.targetPosition.roll = undefined;
});
for (let i = 1; i < this.DronePositions.length - 1; i++) {
let pos1 = this.DronePositions[i];
let pos2 = this.DronePositions[i + 1];
let deltaHeading = pos2.targetPosition.heading - pos1.targetPosition.heading;
pos2.targetPosition.roll = deltaHeading / 1.5;
}
}
效果
主要是飛機(jī)的朝向和轉(zhuǎn)彎時(shí)的翻滾，俯仰角這里沒(méi)體現(xiàn)。
文章來(lái)源地址http://www.zghlxwxcb.cn/news/detail-844251.html
遇到的問(wèn)題
- 插值計(jì)算的問(wèn)題，就是設(shè)置的坐標(biāo)集合，是拆線，最好把它插值成平滑曲線，但是Cesium自帶的插值，有時(shí)間參數(shù)，而我想僅僅通過(guò)經(jīng)緯度集合來(lái)插值。
- 我寫(xiě)的計(jì)算roll的方法有問(wèn)題，不支持轉(zhuǎn)彎大于90度的情況，花了一些時(shí)間，沒(méi)搞定。轉(zhuǎn)彎小于90度，湊合用，測(cè)試了幾組數(shù)據(jù)沒(méi)問(wèn)題，但仍不確定有沒(méi)有BUG。嚴(yán)格來(lái)講，根據(jù)這些參數(shù)，這個(gè)roll是算不出來(lái)的，但是，該算法要求根據(jù)飛機(jī)的轉(zhuǎn)彎半徑及方向，給出一個(gè)相對(duì)合理的roll值。
拋磚引玉，有沒(méi)有高手給個(gè)提示，插值問(wèn)題怎么解決？roll的正確的通用的計(jì)算方法？
到了這里，關(guān)于Cesium 根據(jù)飛機(jī)航線計(jì)算飛機(jī)的Heading(偏航角)、Pitch(俯仰角)、Roll(翻滾角)的文章就介紹完了。如果您還想了解更多內(nèi)容，請(qǐng)?jiān)谟疑辖撬阉鱐OY模板網(wǎng)以前的文章或繼續(xù)瀏覽下面的相關(guān)文章，希望大家以后多多支持TOY模板網(wǎng)！
