Flexible drive system – simple, yet clever

HepcoMotionvisit website


Robotronic AG, the Swiss sole agency for Mitsubishi robots, focuses on individual automation systems. For the specialist’s self-developed robot cell ‘MRT’ (Modular Robot Technology), a feeding system for the pharmaceutical packaging industry, HepcoMotion linear systems were the choice. The combination of Robotronic’s modular design and HepcoMotion’s linear systems offers an individual product, ready for serial production.

Flexible drive system – simple, yet cleverMike Weber, general manager of Robotronic AG, and his team in Winterthur invested 3 years of hard work into developing the MRT robot cell. His philosophy: finding easy and cost-efficient approaches for complex tasks.

Early in the development phase Mike Weber was looking for a very flexible drive system. One of his business partners made him aware of HepcoMotion, who also builds customised special components. The family-run company Hepco Slide Systems Ltd (trade name HepcoMotion) has developed and distributed linear motion systems for more than 40 years. Weber analysed the products, which can be used separately not only as individual units but also combined with different technologies to build linear, rotary and continuous systems. From the beginning he was impressed by the cleverness of the systems, which can be customised individually for most diverse requirements.

Weber prefers continuing business with the same supplier, so that he knows the systems through and through. That is why it is so important for Weber to collaborate with companies such as HepcoMotion – to further standardise their modular system and reduce the risk of failures and quality problems.

Now that the MRT system is ready for serial production, the proof of concept is taking place at a well-known international customer in the pharmaceutical industry. Small glass vials in packs of five are moved onto a transport system by the new robot cell, where they are packed into blisters every second and afterwards put into a cartoning machine.

This is carried out by two parallel working robots, each of which equipped with a double gripper to pick up 2 × 5 vials and put them into blisters. The trays containing the 10 vials are transported by an accurate screw drive; the carriages are directed and driven by a belt between V-slides. A Mitsubishi servo motor controls the position of the blisters.

Mike Weber explains that he was looking for a system that works very precisely. On the one hand the vials are made of fragile glass and can break easily; on the other hand, the handling was supposed to be working both rapidly and precisely together with the robots and the feeding system. This is necessary to guarantee high efficiency and avoid problems such as machine breakdowns. According to Weber, HepcoMotion’s system meets these challenges. Its design works at high speed and still is mechanically robust and very accurate.

Custom-made design

Stefan Kaufmann, HepcoMotion’s salesman for Switzerland, explains the new DTS2 system which was used here: “The Dynamic Track System ‘DTS2’ uses a screw drive that positions the carriage exactly where it is needed. In this special application, six carriages are placed with a positional accuracy of +/-0.2mm. An extra long drive screw was built for this custom-made design so six carriages can be driven by one screw. The carriages themselves (21 all in all) are fixed onto slides. On the outside these carriages are connected with a belt, just like a railway.”

In Weber’s opinion, another reason why the modular design and the DTS2 system match so well is the possibility to combine it with Mitsubishi motors. Standard motors are often used together with ready designed systems – with HepcoMotion’s product, they can work with their own individual motors.

When using Mitsubishi motors, up to eight extra servo axes can be driven directly by the robot system. The additional axis is designed for the robot and operated by the robot controller. This is an interpolating task which must be carried out with high positional accuracy, another important aspect.

This system offers a very flexible but at the same time robust and easy-to-handle technology whose mechanical construction guarantees high positional accuracy during a long system life.

Weber plans to use HepcoMotion products as standard components for their modular systems. Using these components, they are able to be more dynamic and drive the screw with higher speed without risk of the belt skipping. Weber and his team compared HepcoMotion products with those of competitors. They are convinced that the quality guarantees a highly functional and low-maintenance system for their own customers – and all this for decades.

To learn more about linear systems from HepcoMotion, please visit the website at

© Copyright 2006-14 The Engineering Network Ltd.