ur_kin.cpp
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00001 #include <ur_kinematics/ur_kin.h>
00002 
00003 namespace ur_kinematics {
00004 
00005   void forward(const double* q, double* T) {
00006     double s1 = sin(*q), c1 = cos(*q); q++;
00007     double q234 = *q, s2 = sin(*q), c2 = cos(*q); q++;
00008     double s3 = sin(*q), c3 = cos(*q); q234 += *q; q++;
00009     q234 += *q; q++;
00010     double s5 = sin(*q), c5 = cos(*q); q++;
00011     double s6 = sin(*q), c6 = cos(*q); 
00012     double s234 = sin(q234), c234 = cos(q234);
00013     *T = ((c1*c234-s1*s234)*s5)/2.0 - c5*s1 + ((c1*c234+s1*s234)*s5)/2.0; T++;
00014     *T = (c6*(s1*s5 + ((c1*c234-s1*s234)*c5)/2.0 + ((c1*c234+s1*s234)*c5)/2.0) - 
00015           (s6*((s1*c234+c1*s234) - (s1*c234-c1*s234)))/2.0); T++;
00016     *T = (-(c6*((s1*c234+c1*s234) - (s1*c234-c1*s234)))/2.0 - 
00017           s6*(s1*s5 + ((c1*c234-s1*s234)*c5)/2.0 + ((c1*c234+s1*s234)*c5)/2.0)); T++;
00018     *T = ((d5*(s1*c234-c1*s234))/2.0 - (d5*(s1*c234+c1*s234))/2.0 - 
00019           d4*s1 + (d6*(c1*c234-s1*s234)*s5)/2.0 + (d6*(c1*c234+s1*s234)*s5)/2.0 - 
00020           a2*c1*c2 - d6*c5*s1 - a3*c1*c2*c3 + a3*c1*s2*s3); T++;
00021     *T = c1*c5 + ((s1*c234+c1*s234)*s5)/2.0 + ((s1*c234-c1*s234)*s5)/2.0; T++;
00022     *T = (c6*(((s1*c234+c1*s234)*c5)/2.0 - c1*s5 + ((s1*c234-c1*s234)*c5)/2.0) + 
00023           s6*((c1*c234-s1*s234)/2.0 - (c1*c234+s1*s234)/2.0)); T++;
00024     *T = (c6*((c1*c234-s1*s234)/2.0 - (c1*c234+s1*s234)/2.0) - 
00025           s6*(((s1*c234+c1*s234)*c5)/2.0 - c1*s5 + ((s1*c234-c1*s234)*c5)/2.0)); T++;
00026     *T = ((d5*(c1*c234-s1*s234))/2.0 - (d5*(c1*c234+s1*s234))/2.0 + d4*c1 + 
00027           (d6*(s1*c234+c1*s234)*s5)/2.0 + (d6*(s1*c234-c1*s234)*s5)/2.0 + d6*c1*c5 - 
00028           a2*c2*s1 - a3*c2*c3*s1 + a3*s1*s2*s3); T++;
00029     *T = ((c234*c5-s234*s5)/2.0 - (c234*c5+s234*s5)/2.0); T++;
00030     *T = ((s234*c6-c234*s6)/2.0 - (s234*c6+c234*s6)/2.0 - s234*c5*c6); T++;
00031     *T = (s234*c5*s6 - (c234*c6+s234*s6)/2.0 - (c234*c6-s234*s6)/2.0); T++;
00032     *T = (d1 + (d6*(c234*c5-s234*s5))/2.0 + a3*(s2*c3+c2*s3) + a2*s2 - 
00033          (d6*(c234*c5+s234*s5))/2.0 - d5*c234); T++;
00034     *T = 0.0; T++; *T = 0.0; T++; *T = 0.0; T++; *T = 1.0;
00035   }
00036 
00037   int inverse(const double* T, double* q_sols, double q6_des) {
00038     int num_sols = 0;
00039     double T02 = -*T; T++; double T00 =  *T; T++; double T01 =  *T; T++; double T03 = -*T; T++; 
00040     double T12 = -*T; T++; double T10 =  *T; T++; double T11 =  *T; T++; double T13 = -*T; T++; 
00041     double T22 =  *T; T++; double T20 = -*T; T++; double T21 = -*T; T++; double T23 =  *T;
00042 
00044     double q1[2];
00045     {
00046       double A = d6*T12 - T13;
00047       double B = d6*T02 - T03;
00048       double R = A*A + B*B;
00049       if(fabs(A) < ZERO_THRESH) {
00050         double div;
00051         if(fabs(fabs(d4) - fabs(B)) < ZERO_THRESH)
00052           div = -SIGN(d4)*SIGN(B);
00053         else
00054           div = -d4/B;
00055         double arcsin = asin(div);
00056         if(fabs(arcsin) < ZERO_THRESH)
00057           arcsin = 0.0;
00058         if(arcsin < 0.0)
00059           q1[0] = arcsin + 2.0*PI;
00060         else
00061           q1[0] = arcsin;
00062         q1[1] = PI - arcsin;
00063       }
00064       else if(fabs(B) < ZERO_THRESH) {
00065         double div;
00066         if(fabs(fabs(d4) - fabs(A)) < ZERO_THRESH)
00067           div = SIGN(d4)*SIGN(A);
00068         else
00069           div = d4/A;
00070         double arccos = acos(div);
00071         q1[0] = arccos;
00072         q1[1] = 2.0*PI - arccos;
00073       }
00074       else if(d4*d4 > R) {
00075         return num_sols;
00076       }
00077       else {
00078         double arccos = acos(d4 / sqrt(R)) ;
00079         double arctan = atan2(-B, A);
00080         double pos = arccos + arctan;
00081         double neg = -arccos + arctan;
00082         if(fabs(pos) < ZERO_THRESH)
00083           pos = 0.0;
00084         if(fabs(neg) < ZERO_THRESH)
00085           neg = 0.0;
00086         if(pos >= 0.0)
00087           q1[0] = pos;
00088         else
00089           q1[0] = 2.0*PI + pos;
00090         if(neg >= 0.0)
00091           q1[1] = neg; 
00092         else
00093           q1[1] = 2.0*PI + neg;
00094       }
00095     }
00097 
00099     double q5[2][2];
00100     {
00101       for(int i=0;i<2;i++) {
00102         double numer = (T03*sin(q1[i]) - T13*cos(q1[i])-d4);
00103         double div;
00104         if(fabs(fabs(numer) - fabs(d6)) < ZERO_THRESH)
00105           div = SIGN(numer) * SIGN(d6);
00106         else
00107           div = numer / d6;
00108         double arccos = acos(div);
00109         q5[i][0] = arccos;
00110         q5[i][1] = 2.0*PI - arccos;
00111       }
00112     }
00114 
00115     {
00116       for(int i=0;i<2;i++) {
00117         for(int j=0;j<2;j++) {
00118           double c1 = cos(q1[i]), s1 = sin(q1[i]);
00119           double c5 = cos(q5[i][j]), s5 = sin(q5[i][j]);
00120           double q6;
00122           if(fabs(s5) < ZERO_THRESH)
00123             q6 = q6_des;
00124           else {
00125             q6 = atan2(SIGN(s5)*-(T01*s1 - T11*c1), 
00126                        SIGN(s5)*(T00*s1 - T10*c1));
00127             if(fabs(q6) < ZERO_THRESH)
00128               q6 = 0.0;
00129             if(q6 < 0.0)
00130               q6 += 2.0*PI;
00131           }
00133 
00134           double q2[2], q3[2], q4[2];
00136           double c6 = cos(q6), s6 = sin(q6);
00137           double x04x = -s5*(T02*c1 + T12*s1) - c5*(s6*(T01*c1 + T11*s1) - c6*(T00*c1 + T10*s1));
00138           double x04y = c5*(T20*c6 - T21*s6) - T22*s5;
00139           double p13x = d5*(s6*(T00*c1 + T10*s1) + c6*(T01*c1 + T11*s1)) - d6*(T02*c1 + T12*s1) + 
00140                         T03*c1 + T13*s1;
00141           double p13y = T23 - d1 - d6*T22 + d5*(T21*c6 + T20*s6);
00142 
00143           double c3 = (p13x*p13x + p13y*p13y - a2*a2 - a3*a3) / (2.0*a2*a3);
00144           if(fabs(fabs(c3) - 1.0) < ZERO_THRESH)
00145             c3 = SIGN(c3);
00146           else if(fabs(c3) > 1.0) {
00147             // TODO NO SOLUTION
00148             continue;
00149           }
00150           double arccos = acos(c3);
00151           q3[0] = arccos;
00152           q3[1] = 2.0*PI - arccos;
00153           double denom = a2*a2 + a3*a3 + 2*a2*a3*c3;
00154           double s3 = sin(arccos);
00155           double A = (a2 + a3*c3), B = a3*s3;
00156           q2[0] = atan2((A*p13y - B*p13x) / denom, (A*p13x + B*p13y) / denom);
00157           q2[1] = atan2((A*p13y + B*p13x) / denom, (A*p13x - B*p13y) / denom);
00158           double c23_0 = cos(q2[0]+q3[0]);
00159           double s23_0 = sin(q2[0]+q3[0]);
00160           double c23_1 = cos(q2[1]+q3[1]);
00161           double s23_1 = sin(q2[1]+q3[1]);
00162           q4[0] = atan2(c23_0*x04y - s23_0*x04x, x04x*c23_0 + x04y*s23_0);
00163           q4[1] = atan2(c23_1*x04y - s23_1*x04x, x04x*c23_1 + x04y*s23_1);
00165           for(int k=0;k<2;k++) {
00166             if(fabs(q2[k]) < ZERO_THRESH)
00167               q2[k] = 0.0;
00168             else if(q2[k] < 0.0) q2[k] += 2.0*PI;
00169             if(fabs(q4[k]) < ZERO_THRESH)
00170               q4[k] = 0.0;
00171             else if(q4[k] < 0.0) q4[k] += 2.0*PI;
00172             q_sols[num_sols*6+0] = q1[i];    q_sols[num_sols*6+1] = q2[k]; 
00173             q_sols[num_sols*6+2] = q3[k];    q_sols[num_sols*6+3] = q4[k]; 
00174             q_sols[num_sols*6+4] = q5[i][j]; q_sols[num_sols*6+5] = q6; 
00175             num_sols++;
00176           }
00177 
00178         }
00179       }
00180     }
00181     return num_sols;
00182   }
00183 };
00184 
00185 
00186 #define IKFAST_HAS_LIBRARY
00187 #include <ur_kinematics/ikfast.h>
00188 using namespace ikfast;
00189 
00190 // check if the included ikfast version matches what this file was compiled with
00191 #define IKFAST_COMPILE_ASSERT(x) extern int __dummy[(int)x]
00192 IKFAST_COMPILE_ASSERT(IKFAST_VERSION==61);
00193 
00194 #ifdef IKFAST_NAMESPACE
00195 namespace IKFAST_NAMESPACE {
00196 #endif
00197 
00198 void to_mat44(double * mat4_4, const IkReal* eetrans, const IkReal* eerot)
00199 {
00200     for(int i=0; i< 3;++i){
00201         mat4_4[i*4+0] = eerot[i*3+0];
00202         mat4_4[i*4+1] = eerot[i*3+1];
00203         mat4_4[i*4+2] = eerot[i*3+2];
00204         mat4_4[i*4+3] = eetrans[i];
00205     }
00206     mat4_4[3*4+0] = 0;
00207     mat4_4[3*4+1] = 0;
00208     mat4_4[3*4+2] = 0;
00209     mat4_4[3*4+3] = 1;
00210 }
00211 
00212 void from_mat44(const double * mat4_4, IkReal* eetrans, IkReal* eerot)
00213 {
00214     for(int i=0; i< 3;++i){
00215         eerot[i*3+0] = mat4_4[i*4+0];
00216         eerot[i*3+1] = mat4_4[i*4+1];
00217         eerot[i*3+2] = mat4_4[i*4+2];
00218         eetrans[i] = mat4_4[i*4+3];
00219     }
00220 }
00221 
00222 
00223 IKFAST_API bool ComputeIk(const IkReal* eetrans, const IkReal* eerot, const IkReal* pfree, IkSolutionListBase<IkReal>& solutions) {
00224   if(!pfree) return false;
00225 
00226   int n = GetNumJoints();
00227   double q_sols[8*6];
00228   double T[16];
00229 
00230   to_mat44(T, eetrans, eerot);
00231 
00232   int num_sols = ur_kinematics::inverse(T, q_sols,pfree[0]);
00233 
00234   std::vector<int> vfree(0);
00235 
00236   for (int i=0; i < num_sols; ++i){
00237     std::vector<IkSingleDOFSolutionBase<IkReal> > vinfos(n);
00238     for (int j=0; j < n; ++j) vinfos[j].foffset = q_sols[i*n+j];
00239     solutions.AddSolution(vinfos,vfree);
00240   }
00241   return num_sols > 0;
00242 }
00243 
00244 IKFAST_API void ComputeFk(const IkReal* j, IkReal* eetrans, IkReal* eerot)
00245 {
00246     double T[16];
00247     ur_kinematics::forward(j,T);
00248     from_mat44(T,eetrans,eerot);
00249 }
00250 
00251 IKFAST_API int GetNumFreeParameters() { return 1; }
00252 IKFAST_API int* GetFreeParameters() { static int freeparams[] = {5}; return freeparams; }
00253 IKFAST_API int GetNumJoints() { return 6; }
00254 
00255 IKFAST_API int GetIkRealSize() { return sizeof(IkReal); }
00256 
00257 #ifdef IKFAST_NAMESPACE
00258 } // end namespace
00259 #endif
00260 
00261 #ifndef IKFAST_NO_MAIN
00262 
00263 using namespace std;
00264 using namespace ur_kinematics;
00265 
00266 int main(int argc, char* argv[])
00267 {
00268   double q[6] = {0.0, 0.0, 1.0, 0.0, 1.0, 0.0};
00269   double* T = new double[16];
00270   forward(q, T);
00271   for(int i=0;i<4;i++) {
00272     for(int j=i*4;j<(i+1)*4;j++)
00273       printf("%1.3f ", T[j]);
00274     printf("\n");
00275   }
00276   double q_sols[8*6];
00277   int num_sols;
00278   num_sols = inverse(T, q_sols);
00279   for(int i=0;i<num_sols;i++) 
00280     printf("%1.6f %1.6f %1.6f %1.6f %1.6f %1.6f\n", 
00281        q_sols[i*6+0], q_sols[i*6+1], q_sols[i*6+2], q_sols[i*6+3], q_sols[i*6+4], q_sols[i*6+5]);
00282   for(int i=0;i<=4;i++)
00283     printf("%f ", PI/2.0*i);
00284   printf("\n");
00285   return 0;
00286 }
00287 #endif


ur_kinematics
Author(s): Kelsey Hawkins
autogenerated on Mon Oct 6 2014 08:24:33