IMS-I Integrated Measuring System

November 01, 2014

The newly enhanced IMS-I integrated measuring system from Rexroth achieves maximum linear motion positioning accuracy even in challenging work environments. The compact solution for ball and roller rail systems has an inductive design that offers repeatable accuracy performance equivalent to that of more expensive glass scale systems. The incremental IMS-I provides feedback for distances of up to 4,500mm, and allows several runner blocks to be positioned independently of each other on the same rail.

Whenever cooling lubricant and chips are introduced in the working environment or strong electric and magnetic fields disrupt sensor operation, designers and engineers require a travel measuring system that is as robust as it is accurate. The advanced IMS-I integrated measuring system from Rexroth is a great compact alternative which is rated for a positioning accuracy of 0.25µm.

The integrated measuring system features a high-precision pitch etched into a steel strip. The scale is integrated into the profiled rail and protected by a tightly welded stainless steel strip across the entire rail section length. The tightly welded connection is capable of resisting extreme vibrations and impacts of up to 10 g, and Rexroth also integrates a highly sensitive evaluation electronics system in the runner blocks to facilitate position sensing close to the tool center point. Additional, external accessory attachments are not needed, which allows the integrated measuring system to fit into tight spaces with minimal effort. This, in turn, makes it possible to achieve straightforward, minimal footprint machine designs, and eliminate additional machine bed preparations needed for traditional alternatives.

In advancing the design of the IMS-I, Rexroth optimized the distance between the sensor and scale to further improve the system's ability to withstand the negative impacts of chips, dust, dirt, and contamination. The inductive measuring system operates without physical contact and is therefore a wear-free assembly. Travel paths of up to 4,500mm can be measured with ease; the user can thus position several runner blocks independently of each other on a single profiled rail and the system will detect each position with exacting precision.

Repeatability accuracy levels attain 0.25µm and scale precision is +/-3µm, both of which allow the IMS-I to offer almost identical performance to that of a glass scale. Unlike the latter, the IMS-I with its IP 67 protection rating does not require any additional sealing or further contamination protection, thereby reducing overall system and operating costs. Rexroth integrates the entire IMS-I sensor system into all versions of its ball and roller rail systems to minimize assembly and servicing effort. Thanks to Rexroth's interchangeable rail system design, all runner blocks of corresponding sizes and configurations can be mounted to profiled rails of different accuracy classes, along with the IMS-I. Not only does this simplify the logistics of the commissioning process, but also makes exchange and replacement easy to minimize machine downtime.

The high level of accuracy and robust design of the IMS-I system make it suitable for a range of industrial applications, including those that involve positioning laser cutters, synchronizing ram or plunger units in presses, extracting PET bottles at high speeds, and assisting with woodworking tasks as well as 3D printer processes that produce abrasive dust. The IMS-I comes preconfigured for direct connection to IndraDrive servo drives from Rexroth and all other commonly available servo drive assemblies, and is able to handle both analog (1 Vss) and digital (TTL) signal types.

Related Glossary Terms

  • abrasive


    Substance used for grinding, honing, lapping, superfinishing and polishing. Examples include garnet, emery, corundum, silicon carbide, cubic boron nitride and diamond in various grit sizes.

  • pitch


    1. On a saw blade, the number of teeth per inch. 2. In threading, the number of threads per inch.