Target vehicle detection

A system, comprising a computer including a processor and a memory, the memory storing instructions executable by the processor to:

• identify a lateral virtual boundary for a host vehicle based on a lateral distance between the host vehicle and a target vehicle, a longitudinal distance between the host vehicle and the target vehicle, and a speed of the target vehicle relative to the host vehicle;
• identify a forward virtual boundary for the host vehicle based on the longitudinal distance between the host vehicle and the target vehicle;
• determine a lateral constraint value of the lateral virtual boundary based on a lateral boundary speed, the lateral boundary speed based on a heading angle of the host vehicle;
• determine a forward constraint value of the forward virtual boundary based on the heading angle of the host vehicle;
• determine a lane boundary and a lane constraint value based on the lane boundary;
• determine a lane boundary acceleration based on the heading angle of the host vehicle and a current steering angle of the host vehicle;
• determine a longitudinal acceleration and a to-be-attained steering angle based on the lateral and forward virtual boundaries and the lateral and forward constraint values, wherein the to-be-attained steering angle is determined further based on the lane constraint value and a lane boundary acceleration;
• and
• actuate one or both of a steering component or a brake based on the longitudinal acceleration and the steering angle.