1.4 计算观测值的权
2?0将上表中的边长观测值代入测距精度公式:?S?a?bSi PS?2,算的各边的测距精度?S,并设
?Siiii?0?10mm,由此算得各条边的权,其结果均列于下表中。
表1-3 各边测距精度及权 边号 1 1.29 2 8.2 1.49 3 10.8 0.86 4 8.5 1.38 5 8.7 1.32 6 11.7 0.73 7 8.6 1.35 8 10.5 0.91 9 10.5 0.91 10 8.4 1.42 11 8.5 1.38 12 11.9 0.71 13 10.2 0.96 8.8 ?(mm)P 1.5 组成法方程 ??BTPl,BTPl及其解x?i列于下表中, ?i、yBTPBx表1-4 坐标平差值
a b c d e f g h ?1 a/x-0.0167 3.1428 0.2578 -0.0005 0.0254 -1.1122 -0.5851 -0.5384 0.3039 ?1 b/y-0.0474 0.2578 3.1472 0.0254 -1.3794 -0.5851 -0.3078 0.3039 -0.1716 ?2 c/x-0.0816 -0.0005 0.0254 2.0447 -0.0815 -0.9704 0.5825 0.0000 0.0000 ?2 d/y0.1004 0.0254 -1.3794 -0.0815 2.2452 0.5825 -0.3497 0.0000 0.0000 ?3 e/x-0.3508 -1.1122 -0.5851 -0.9704 0.5825 3.5749 0.0070 -0.1386 0.3269 ?3 f/y0.1416 -0.5851 -0.3078 0.5825 -0.3497 0.0070 2.3352 0.3269 -0.7714 ?4 g/x1.0258 -0.5384 0.3039 0.0000 0.0000 -0.1386 0.3269 2.3070 0.2362 ?4 h/y1.0276 0.3039 -0.1716 0.0000 0.0000 0.3269 -0.7714 0.2362 1.6531 BTPl 0.0052 0.0031 0.2466 0.0432 -0.8750 -0.1870 2.6988 1.7201 ?1求NBB?(BTPB)?1,列于表中。表1-5 参数的协因数
0.4210 -0.0589 0.0794 ?1= NBB-0.0589 0.5146 -0.0645 0.3540 -0.0314 0.2010 -0.1306 0.1829 0.0794 -0.0645 0.6706 -0.1175 0.2380 -0.2543 0.0980 -0.2011 -0.0828 0.3540 -0.1175 0.73745 -0.1457 0.2575 -0.1337 0.2201 0.1738 -0.0314 0.2380 -0.1457 0.4393 -0.123 0.1084 -0.1948 0.0020 0.2010 -0.2543 0.25752 -0.1226 0.7157 -0.1762 0.4039 0.1300 -0.1306 0.0980 -0.1337 0.1084 -0.1762 0.53477 -0.2175 -0.1355 0.1829 -0.2011 0.22010 -0.1948 0.4039 -0.2175 0.9069 -0.0828 0.17382 0.0020 0.1300 -0.1355 1.6 平差值计算 ??X?x?i计算: 1.6.1坐标平差值 按公式Xii??X0?x??Y0?y?1=48580.268m Y?1=60500.500m X1111??X0?x?2=48681.382m X22??Y0?y?2=55018.290m Y22??X0?x?3=43767.189m X33??X0?x?4=40843.321m X44
??Y0?y?3=57968.610m Y33??Y0?y?4=64867.980m Y445
1.6.2边长平差值计算 按公式S??S?V计算: S?1?S01?v?1=5760.711m S?2?S02?v?2=5187.344m S?3?S03?v?3=7838.878m S?4?S04?v?4=5483.143m S?5?S05?v?5=5731.813m S?6?S06?v?6=8719.088m S?7?S07?v?7=5598.642m S?8?S08?v?8=7494.959m S?9?S09?v?9=7493.356m S?10?S010?v?10=5438.400m S?11?S011?v?11=5486.903m S?12?S012?v?12=8884.550m S?13?S013?v?13=7228.488m 精度计算
1.7.1单位权中误差:
?VT?PV0.6620?n?t=13?8=0.36dm 1.7.2待定点坐标中误差:
N?1BB)取得参数的权倒数,计算待定点坐标点点位中误差:
??X1?0.360.42?0.23dm ??Y1?0.360.51?0.26dm ?????2???22P1X1Y1?0.232?0.26?0.35dm
??X2?0.360.67?0.29dm ??Y2?0.360.74?0.31dm ??22P2???X2???Y2?0.292?0.312?0.42dm
??X3?0.360.44?0.24dm ??Y3?0.360.72?0.31dm ??22P3???X3???Y3?0.242?0.312?0.39dm
??X4?0.360.53?0.26dm ??Y4?0.360.91?0.34dm ??22P4???X4???Y4?0.262?0.342?0.43dm
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1.7 由参数的协因数阵(即
第2章 三角网坐标平差
2.在下图所示的测角网中,A,B,C为已知点,P1,P2为待定点,S1~S10为角度观测值,已知点坐标与待定点近似坐标为:
点号 已知坐标/m 点号 近似坐标/m X Y X Y A 883.2892 259.1385 P1 777.416 320.647 B 640.2838 144.1899 P2 844.971 504.160 C 612.0508 463.8277 同精度观测值为:
编号 观测值 观测值 o ˊ \编号 o ˊ \1 55 28 13.2 6 59 57 57.2 2 97 41 53.9 7 69 19 22.1 3 93 02 06.0 8 99 56 38.2 4 44 03 51.6 9 29 05 51.3 5 50 42 44.3 10 50 57 29.0 是按坐标平差法求:
(1) 误差方程及法方程;
(2) 待定点最或是坐标及点位中误差; (3) 观测值改正值及平差值。
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解:由题意有:t=4,设待定点P1,P2的坐标的平差值为参数,即P1?(X?1,Y?1),P2?(X?2,Y?2)。 2.1 测角网函数模型:
L?1??AB???A1 L?2???1A???1B L?3???1B???1C L?4???C1???1CB L?5???C2???C1 L?6???21???2C L?7???1C???12 L?8???12???1A L?9???2A???21 L?10???A1???A2 其中L?i?Li?Vi,X?0i?Xi?x???i,Y?0Yj?Yii?Yi?y?i,?ij?arctanX?X,??arctanYjY?iij?jiX?j?X?,
i00?0?arctanYj?YiijX00,li?Li?L0i,将以上式子带入并线性化得:
j?XiV????Y0A1???XA11?(S02x??01?A1)(S02y?1?l1 A1)V?Y01A????Y01B2?(???(S0)2?)x????X01A?X01B1?(?02)y?1?l2 1A(S0B)21(S)2????1A(S01B)0V?Y01B????Y1C???X01B????X01C3?(???(S02?1B)(S01C)2)x?1?(?(S02?1B)(S02)y?1?l3 1C)V?Y0C1????X0C14?????(S0)2x?1?0C1(S)2y?1?l4 C1V????Y0C1???XC1???Y0C2????X05?(S02x?01?C1)?(S02y?1??C1)(S02x?C22?y?l5 C2)(S02C2)?2V??????Y021?????X0x21????X0????X0212C6(S0)21?y???Y211?(??0?????Y02C)x2?()y?2?l6 21(S021)2(S021)2(S0)2?2C(S0)2?21(S0C)22VY01C????Y0????X07?(????(S0?12?12????Y012???X121C)2(S0)2)x?????X01C1?(12(S0)21C(S0)2)y?1?02x??02?2y?2?l7 12(S12)(S012)00V????Y0?????Y1A)x?????X01212????X1A??Y12?X128?((S0)21?(12(S0)21A(S0)2?12(S0)2)y???01?1A(S0)2????0x2?12(S0)2y?2?l8 12V????Y021????X0????Y021????X09?(S0)2x?211?21(S0)2y?????Y02A1?(21(S0)2?2A(S0)2)?????X0x2A2?(?21)y?l9 21(S02A)2(S0)2?221V????Y0A1????X0A1??YA2????X0A210??(S0)2x?1?x?2?A1(S02y?1???0A1)(S02A2)(S02y?2?l10 A2)
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2.2 坐标方位角计算
2.2.1 近似坐标方位角计算
按公式??arctan0ijYj0?Yi0X?X0j0i得:
近似坐标方位角
方向 近似坐标方位角 o ˊ \329 50 41.8 232 08 51.8 139 06 45.0 方向 近似坐标方位角 o ˊ \69 47 25.0 278 53 17.9 189 49 26.0 P1A P1B P1P2 P2A P2CP1C 2.2.2 坐标方位角计算 按公式?ij?arctanYj?YiXj?Xi得:aAB?20518?55.8??,?BC?95?02?51.8??
?2.3 近似坐标增量、近似边长与误差方程系数
000222按公式?Yp, ,,aij??Y?Y?X?X?X(S)?(X?X)?(Y?Y)jjPpjjPpjjPjPiiiiiii????Yij002(Sij),
bij??0????Xij(S)02ij得:
误差方程系数表 ?Yij0 方向 0 ?Xij02(Sij) aij?(m) (m) ????Yij002(Sij)?100 bij??0????Xij02(Sij)?100 (m2) P1A -61.5085 105.8732 14992.43005 P1B -176.4571 -137.1322 49942.34842 P1C 143.1807 -165.3652 47846.36222 -8.4623 -7.2878 6.1725 9.8984 -8.2173 -1.4888 -14.5660 5.6636 7.1289 -3.6438 -1.2851 8.5978 P1P2 183.5130 67.5550 38.3182 38240.69919 61503.81991 P2A -245.0215 P2C -40.3323 -232.9202 55878.51399
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