Iowa law requires polling places in Iowa to be accessible to persons with disabilities. Each polling place will have a ballot-marking machine that allows a voter with blindness or visual impairment to vote privately. The ballot-marking machine may be used by any voter.
A voter may choose another person to assist the voter in voting except the voter’s employer, employer’s agent, an officer or agent of the voter’s union, a candidate listed on the ballot. If a voter requests assistance from a precinct election official, two precinct officials – one Democrat and one Republican – will assist the voter together. A voter who is physically unable to enter a polling place has the right to vote in the voter’s vehicle.
You can find more information here: sos.iowa.gov/disabilities