求R的表达式 其中 m m1 m2为中间变量需要去除m1 = sqrtrc_para-dist_axis_wheelrc_para-dist_axis_wheel - rc_para-dist_wheel_wheel2rc_para-dist_wheel_wheel2;m2 = sqrt R2+rc_para-wheel_radiusR2+rc_para-wheel_radius

R = sqrt( ((m1+m2)(m1+m2) - mm) + (rc_para->dist_axis1_axis2/2-rc_para->dist_axis_wheel) *(rc_para->dist_axis1_axis2/2-rc_para->dist_axis_wheel) ) - rc_para->wheel_radius/2;