I posted a question on Modbus TCP that covers what I am trying to do. However, to expand on it here, I am building a custom gripper to lift plants out of our vertical hydroponics system. Initially I am using various arduino boards to work out the bugs. I will have some of the arduino hardware on the gripper and some next to the control box. Once I have worked it out, I will have a custom board made to contain all the hardware within the gripper. I will post some pictures and video shortly.