Question

我一直在跟tutorial一起跟踪，它模拟了地球，金星和太阳。代码运行正常。但是，我正在尝试对围绕地球的卫星轨道进行建模，其中地球是其“宇宙”在位置（0,0）的中心。我的卫星在切线上飞行时遇到了问题，但我不确定为什么。

import numpy as np
import numpy as np
class Planet():
    def __init__(self,vx=0.0,vy=0.0,px=0.0,py=0.0,mass=0.0):
        self.vx=vx
        self.vy=vy
        self.px=px
        self.py=py
        self.mass = mass
        
def attract(p1,p2,grav=6.67428e-11):
    dx = p1.px - p2.px
    dy = p1.py - p2.py
    d = np.sqrt(dx**2 + dy**2)
    force = (grav * p1.mass * p2.mass)/d**2
    theta = math.atan2(dy,dx)
    fx = math.cos(theta)*force
    fy = math.sin(theta)*force
    return fx,fy

def loop(bodies,epochs=10,timestep=10):
    # compute forces
    forces = {}
    for i in range(0,len(bodies)):
        total_fx = 0
        total_fy = 0
        for j in range(0,len(bodies)):
            if i == j:
                continue
            fx,fy = attract(bodies[i],bodies[j])
            total_fx += fx
            total_fy += fy
        forces[i] = (total_fx,total_fy)
    #apply forces 
    sat_tups = []
    for e in range(epochs):
        for i in range(len(bodies)):
            if bodies[i] == satellite:
                sat_tups.append((bodies[i].px,bodies[i].py))            
            fx,fy = forces[i]
            bodies[i].vx += (fx/bodies[i].mass*timestep)
            bodies[i].vy += (fy/bodies[i].mass*timestep)
            bodies[i].px += bodies[i].vx*timestep
            bodies[i].py += bodies[i].vy*timestep  

    return sat_tups
        
 

earth = Planet(mass = 5.9742 * 10**24)
satellite = Planet(mass= 3000.0, px= 1414.0, py= 1414.0, vx=2300.0,vy=2300.0)
tups = loop(bodies=[earth,satellite])

tups
>>>
[(1414.0, 1414.0),
 (7050856421.79636, 7050856421.79636),
 (21152543437.38908, 21152543437.38908),
 (42305062460.77817, 42305062460.77817),
 (70508413491.96361, 70508413491.96361),
 (105762596530.9454, 105762596530.9454),
 (148067611577.72357, 148067611577.72357),
 (197423458632.2981, 197423458632.2981),
 (253830137694.66898, 253830137694.66898),
 (317287648764.83624, 317287648764.83624)]

我不确定是什么问题。也许以（0,0）为中心的地球根本行不通。或者，也许这些物理定律仅适用于尺寸相对相似的物体（其他更复杂的规则正在发挥作用）。

要回答此问题，请解决导致卫星飞离的原因？（我猜想它会撞到地球上，而不是被弹开了。）

在python中模拟围绕地球的卫星轨道？

0 个答案: