But Baptiste tried to flee from the front passenger seat via gardens.
He took off his clothes as he ran, but was soon arrested.
Inner London Crown Court heard how the men carried out the incident at 6.50pm on July 3 last year in Dulwich.
Inner London Crown Court
The Metropolitan Police said the woman in her 30s was “terrified”.
Baptiste, of Juniper Road, Crawley, was jailed for three years and 11 months for attempted robbery.
Roche, of Melbourne Grove, Southwark, was jailed for four years and three months, while Robinson, of Grange Road, Croydon, was jailed for three years.
Met Police Detective Sergeant Chris Shepherd said: “This case of mistaken identity was an absolutely terrifying ordeal for the victim and her three young children.