3 types of detentions that are not custodial
1. Traffic stops. Although the driver is unquestionably not free to leave, the courts have held that a driver detained for questioning as part of a traffic stop is not in custody and, therefore, that Miranda warnings are not required.

2. On-street questioning. When police stop a suspect on the street to make reasonable inquiries, that person is not considered "in custody" for Miranda purposes, as he is free at any time to end the questioning and continue on his way.

3. In-home visits. When police visit a person's home to initiate questioning, the suspect is not in custody, and Miranda warnings are not required.
www.justanswer.com/criminal-law/6bd1f-identify-types-detentions-not-custodial.html