Limit rate/min of an agent user or 4 Ips

Hello, I′m having a problem with 4 ips of twitterbot1/0 agent user. They ask for more than 50 url (html, jpg resources) at the same time, like crawling something. It happens always at the same hour and my site falls for a minute more or less.

Is your plugin able to limit the visits per minute from this user agents? I mean, for example 10 visits per minute from the user agent or ips.

Many thanks.