ValueError: expected an expression convertible to a polynomial in Polynomial ring

[Reza Housseini]

Hello

I try to integrate he following (long) integral

    sp.integrate(sp.asin((sp.cos(alpha)*sp.sqrt(vx**2+vy**2+R*dotphi*(2*vx*sp.sin(phi)-2*vy*sp.cos(phi)+R*dotphi)))/(sp.sqrt((vx*sp.cos(phi)+vy*sp.sin(phi))**2+(vx*sp.sin(phi)-vy*sp.cos(phi)+R*dotphi)**2)))-sp.atan((vx*sp.sin(phi)-vy*sp.cos(phi)+R*dotphi)/(vx*sp.cos(phi)+vy*sp.sin(phi))), (phi,0,2*sp.pi))

and get the error

   ValueError: expected an expression convertible to a polynomial in Polynomial ring

What is the problem here?

Thanks for any hints.

Cheers,

Reza