There are 3 different types of bots: Health, Armor and Ammo bot. They can assist you in great ways.
The health bot, has a charging time of 2 seconds. It also replenishes only 80 health points so be careful about how you use it.
This bot, replenishes the default ammount of starting ammo a weapon has. This is essential for maps that don't have a type of ammo that you need. It too, has a 2 second charge,