Mechanical pruning is nothing new to the fruit industry.

After all, winegrape growers have used machines to prune their vines for several years.

But a group led by Purdue University researcher Peter Wirst wants to make the practice more precise by adding a camera and robotics, according to a news release.

They have received $6 million in grants to automate pruning, which accounts for about 20 percent of labor costs for fruit growers.

The U.S. Department of Agriculture's specialty Crops Research Initiative will provide $3 million, with another $3 million in matching funds from the industry and institutions.

The first part of the project is to improve the prototype of an automated grapevine pruner developed by Vision Robotics of San Diego, a partner in the program.

A tractor pulls the machine over grape vines while cameras capture images of the vines and a computer tells robotic arms where the vines should be pruned.

The pruner is in the prototype phase.

Researchers hope to move it to the commercial arena.

The group also will start work on an automated apple tree pruner by trying to model trees and how they should be pruned.

Then they'll start work on a prototype robotic pruner, but actual construction of a robotic pruner will have to wait for future grants.

"Apple trees are more complex and will take more time," Hirst said in the release. "But once we have that, it should be much smaller steps to translating the work for other fruits such as plums, peaches and cherries."