Kyler, here is the UTM conversion i use. Works to the millimeter - even to convert back. If you want the conversion back, i can post that too. Its written in C# but can easily be changed to whatever language.
//private double pi = 3.141592653589793238462643383279502884197169399375;
private double sm_a = 6378137.0;
private double sm_b = 6356752.314;
private double UTMScaleFactor = 0.9996;
//private double UTMScaleFactor2 = 1.0004001600640256102440976390556;
public void DecDeg2UTM()
{
zone = Math.Floor((longitude + 180.0) * 0.16666666666666666666666666666667) + 1;
GeoUTMConverterXY(latitude * 0.01745329251994329576923690766743,
longitude * 0.01745329251994329576923690766743);
}
// return (degrees * 0.01745329251994329576923690766743);
private double ArcLengthOfMeridian(double phi)
{
double alpha, beta, gamma, delta, epsilon, n;
double result;
n = (sm_a - sm_b) / (sm_a + sm_b);
alpha = ((sm_a + sm_b) / 2.0) * (1.0 + (Math.Pow(n, 2.0) / 4.0) + (Math.Pow(n, 4.0) / 64.0));
beta = (-3.0 * n / 2.0) + (9.0 * Math.Pow(n, 3.0) / 16.0) + (-3.0 * Math.Pow(n, 5.0) / 32.0);
gamma = (15.0 * Math.Pow(n, 2.0) / 16.0)
+ (-15.0 * Math.Pow(n, 4.0) / 32.0);
delta = (-35.0 * Math.Pow(n, 3.0) / 48.0)
+ (105.0 * Math.Pow(n, 5.0) / 256.0);
epsilon = (315.0 * Math.Pow(n, 4.0) / 512.0);
result = alpha
* (phi + (beta * Math.Sin(2.0 * phi))
+ (gamma * Math.Sin(4.0 * phi))
+ (delta * Math.Sin(6.0 * phi))
+ (epsilon * Math.Sin(8.0 * phi)));
return result;
}
private double UTMCentralMeridian(double zone)
{
return ((-183.0 + (zone * 6.0)) * 0.01745329251994329576923690766743);
}
private double[] MapLatLonToXY(double phi, double lambda, double lambda0)
{
double[] xy = new double[2];
double N, nu2, ep2, t, t2, l;
double l3coef, l4coef, l5coef, l6coef, l7coef, l8coef;
double tmp;
ep2 = (Math.Pow(sm_a, 2.0) - Math.Pow(sm_b, 2.0)) / Math.Pow(sm_b, 2.0);
nu2 = ep2 * Math.Pow(Math.Cos(phi), 2.0);
N = Math.Pow(sm_a, 2.0) / (sm_b * Math.Sqrt(1 + nu2));
t = Math.Tan(phi);
t2 = t * t;
tmp = (t2 * t2 * t2) - Math.Pow(t, 6.0);
l = lambda - lambda0;
l3coef = 1.0 - t2 + nu2;
l4coef = 5.0 - t2 + 9 * nu2 + 4.0 * (nu2 * nu2);
l5coef = 5.0 - 18.0 * t2 + (t2 * t2) + 14.0 * nu2 - 58.0 * t2 * nu2;
l6coef = 61.0 - 58.0 * t2 + (t2 * t2) + 270.0 * nu2 - 330.0 * t2 * nu2;
l7coef = 61.0 - 479.0 * t2 + 179.0 * (t2 * t2) - (t2 * t2 * t2);
l8coef = 1385.0 - 3111.0 * t2 + 543.0 * (t2 * t2) - (t2 * t2 * t2);
/* Calculate easting (x) */
xy[0] = N * Math.Cos(phi) * l
+ (N / 6.0 * Math.Pow(Math.Cos(phi), 3.0) * l3coef * Math.Pow(l, 3.0))
+ (N / 120.0 * Math.Pow(Math.Cos(phi), 5.0) * l5coef * Math.Pow(l, 5.0))
+ (N / 5040.0 * Math.Pow(Math.Cos(phi), 7.0) * l7coef * Math.Pow(l, 7.0));
/* Calculate northing (y) */
xy[1] = ArcLengthOfMeridian(phi)
+ (t / 2.0 * N * Math.Pow(Math.Cos(phi), 2.0) * Math.Pow(l, 2.0))
+ (t / 24.0 * N * Math.Pow(Math.Cos(phi), 4.0) * l4coef * Math.Pow(l, 4.0))
+ (t / 720.0 * N * Math.Pow(Math.Cos(phi), 6.0) * l6coef * Math.Pow(l, 6.0))
+ (t / 40320.0 * N * Math.Pow(Math.Cos(phi), 8.0) * l8coef * Math.Pow(l, 8.0));
return xy;
}
private void GeoUTMConverterXY(double lat, double lon)
{
double[] xy = MapLatLonToXY(lat, lon, (-183.0 + (zone * 6.0)) * 0.01745329251994329576923690766743);
xy[0] = xy[0] * UTMScaleFactor + 500000.0;
xy[1] = xy[1] * UTMScaleFactor;
if (xy[1] < 0.0)
xy[1] = xy[1] + 10000000.0;
//keep a copy of actual easting and northings
actualEasting = xy[0];
actualNorthing = xy[1];
}
---
[Visit Topic](
https://discourse.ros.org/t/tractobots-my-attempts-at-field-robots/1486/19) or reply to this email to respond.
If you do not want to receive messages from ros-users please use the unsubscribe link below. If you use the one above, you will stop all of ros-users from receiving updates.
______________________________________________________________________________
ros-users mailing list
ros-users@lists.ros.org
http://lists.ros.org/mailman/listinfo/ros-users
Unsubscribe: <
http://lists.ros.org/mailman//options/ros-users>