Reverse motor direction

I have a DC motor and I want to change it's direction when proximity meter output particular voltage.
In other words, I want to conditionally switch motor inputs.

What component you would you suggest me to use? Comparator? Some combination of H-Bridges?

Thank you in advance.

You need a single H-bridge to run the motor in both directions.

You need the 'proximity meter' which I assume puts out a voltage. You can use the Arduino to read the voltage and make decisions so you don't need a comparator or a latch.

depending on the size of the motor there are a bunch of motor sheilds that will make it reverse direction.
I use a pololu Pololu - Dual VNH3SP30 Motor Driver Carrier MD03A to control speed and direction of 2 motors.