A company based in Rotterdam, the Netherlands, has designed and produced a cost-effective automation system for plant irrigation and management in the Netherlands, a major flower producer in Europe. The company is a partnership between automation company Riwo Engine-ing and Emerson CT's Drive Center.
A company based in Rotterdam, the Netherlands, has designed and produced a cost-effective automation system for plant irrigation and management in the Netherlands, a major flower producer in Europe. The company is a partnership between automation company Riwo Engine-ing and Emerson CT's Drive Center.
Emsflower, a Dutch company located across the border from Emsburen, Germany, currently owns 26 hectares of greenhouses and grows around 500 million plants a year, mostly for promotional purposes in discount chain supermarkets, with more than a million plants shipped simultaneously to destinations across Europe.
In the face of this, Riwo Engineering had to meet demanding requirements, as Riwo partner Wim Spit explains succinct: "The new system must perform plant transport, irrigation, pesticide spraying and pest control, decentralized control functions as well as centralized control functions, precise positioning at a distance of 250 meters, delivery of power and water along a length of 150 meters, easy maintenance and at a limited cost."
"In order to position accurately under varying loads, travel at high speeds between locations and minimize downtime, the drive must have a wide frequency control range." Wim Spit adds.
The proposed scheme, which was subsequently tested and accepted, consisted of plastic wheeled carts running on overhead tracks arranged along each 8-metre-wide greenhouse barrier. Each vehicle has two wheels driven by synchronous motors with encoders, which are controlled by a 1.5 kW Unidrive SP AC drive from Emerson CT.
The first task of each trolley is to spray water on the plants according to the program determined by the main computer. Each cart is also used to carry tools, providing additional functionality.
The system is configured in a variety of ways, currently ten treatment modules can be suspended from a sling under a cart for spraying insecticides or fungicides, and different modules are used to insert seedlings in a 16-square-meter planting plot. In addition to requiring additional spraying, the field manager can direct the cart to drive around the greenhouse and transport itself to the location where it needs to work.
Many of the modules are powered by Emerson CT's Unidrive SP drive, communicate with the main drive over CN-Net, and communicate with the main computer over Wi-Fi.
"We loved the Unidrive SP, and the drive proved to be perfect for this application," says Wim Spit. "CT-Net allows multiple drives to be connected to a single main system, on-board programming allows us to provide the level of precision and repeatability our customers require, and the open Modbus-based architecture provides a low-cost interface to the main system - cooling fins on the back of the IP54 control cabinet also proved to be ideal for this environment."
The Unidrive SP is the world's most advanced "solution platform" AC driver that can be configured in 5 operating modes (open and closed loop, vector, servo and regenerative modes), can be connected to most industry standard networks, can be configured for various types of AC motors, including linear motors, and accepts 14 position feedback protocols. It has many plug-in module options for increased connectivity, feedback, extra I/O, and onboard programming.
Wim Spit praises the entrepreneurial spirit of Ben-nie and Tom Kuipers, the father and son who run the sprawling Emsflowe business. Bennie Kuipers has spent his life gardening and running the business, while his son Tom has helped develop the powerful and sophisticated computer control systems used in all aspects of the complex's logistics, planning, production, order fulfillment, administration and people management. Working closely with Riwo Engineering, they had a clear idea and the right approach to make this dream a reality in a very short time.
