5 years ago

MDA Technologies 4/2016

MDA Technologies 4/2016

Micro-motors for

Micro-motors for innovative telescopic solutions To drive the Zippermast, the driving motor had serious constraints in terms of limited space and size, without compromising on the output torque and deliver reliably under unpredictably severe circumstances. remote-controlled caterpillar vehicle with the bobby-car format A stops just in front of the head-high wall. Then, a mast extends upwards from its interior on top of which a small camera is mounted. A few moments later, it has an unhindered view of the events behind the wall. ‘ProgenoX’, the company based in Bavaria, supplies the vehicle for unmanned exploration. The highlight of ProgenoX’s recent launch is the extremely compact “Zippermast” which consists of three interlocked steel tapes according to the zipper principle. A motor from the drive systems specialist Faulhaber provides the unique design with reliable retraction and extension. General Manager at ProgenoX, Frank Woodcock explains “Whoever sees the Zippermast for the first time is amazed at how high it can be extended”. This is mostly because the housing where the mast is hidden is very small: the smallest model, the ZM4, is just 15 cm high and the standard model, the ZM8, is 25 cm. How far the mast can be extended can be seen from the model number – it corresponds to the height in feet. In the case of ZM8, which is easy to carry with its weight of seven kilograms, the mast extends to around two and a half meters. The mast of the ZM40 reaches a height of more than 12 m. comes the developer George Woodruff and his design of the Zippermast into the picture with inspiration from a metallic measuring tape, which is under tension due to its curvature and can therefore be extended without kinking. Woodruff used three steel tapes and interlinked them when extending according to the zipper principle. In this way, the flexible tapes become a stable mast. The three tapes made out of spring-tempered stainless steel are wrapped around coils and arranged in relation to each other at angles of 120 °. A guiding spindle, which is in the middle of this triangle, grips the tapes in the beveled slots provided. The tapes are rolled upwards by the rotation of the guiding spindle. Their jagged outer edges interlock with each other. The ‘Zippermast’ can be extended to any position in-between. No additional locking mechanism is required to hold this position: the weight of the tapes and the load rest on the guiding spindle’s thread which can only be moved by rotation, like the nut on a screw. “When I saw the Zippermast for the first time, I was immediately excited by the design principle”, recollects Frank Woodcock. He acquired the technology in the USA in 2012 and brought it to Germany. He reworked the telescopic mast with his team from ‘ProgenoX’ and got it ready for series production. Customers are mainly the so-called blue-light organizations such as the fire service, emergency service, disaster control, civil defense and the police. They mostly deploy the masts for monitoring and surveillance purposes – hence in the area for which it was originally designed. But the Zippermast has also proven itself to be useful at other tasks, such as inspecting pipes and shafts. Thus, it is used in nuclear power plants in order to search the ventilation systems for cracks and foreign objects. Inspired from a regular measuring tape! Every innovation needs an inspiration, George Woodruff the developer of Zippermast’s innovative telescopic technology found his inspiration in a regular metallic measuring tape. When the American armed forces were in the market looking for innovative solutions for their unmanned exploration activities, they were particularly looking for a compact and robust system. Here About Faulhaber DRIVE TECHNOLOGIES Faulhaber headquartered in Schönaich near Stuttgart in the German state of Baden-Wuerttemberg, is an independent family-run group of companies. Founded in 1947, today Faulhaber offers the most extensive range of miniature and micro drive systems. On the basis of this technological diversity, Faulhaber designs drive solutions that are unique with respect to their precision and reliability in the smallest of spaces. Their main areas of use include production automation and robotics, aerospace, optical systems as well as medicine and laboratory technology. In addition to Germany, Faulhaber has development and production locations in Switzerland, USA, Romania and Hungary. With sales partners and subsidiaries in more than 30 countries around the world, this drive specialist employs more than 1 700 people. MDA Technologies 4/2016

Compact, operationally stable and sturdy Thanks to the coiled tapes, the Zippermast finds space in very small housing. Another advantage of this design: the diameter of the Zippermasts remains constant in any position across its entire length – unlike telescopic masts which consists of components nested into each other. Thus, enough space in the interior of the masts remains to lead the cable through the guiding spindle to the head and be protected from outside influences. Furthermore, its design principle makes the Zippermast extremely stable. This sturdiness is increased further by heat treatment of the steel tapes. To do this, coiled tapes are heated on the coils and subsequently cooled again. The crystal structure of the steel adapts itself to this position and seeks to adopt it. Tension is therefore generated by rolling up the tapes which further stabilizes the mast. Thanks to its stability, the Zippermast can also extend horizontally and be loaded. 01 Innovative and intelligent mast system for the BOS, Homeland Security and security relevant industry markets 02 The compact and mobile design is more favourable for conspirative use 03 DC – micromotor, diameter: 32 mm, length: 72 mm, output torque: 120 mNm Suitable for the high seas and outer space ProgenoX has done a lot to make the Zippermast fit for everyday use. The steel tapes are coated with a special surface coating in order to minimize wear. The guiding spindle is hardened in a heating process, and the electronics are moulded. Furthermore, the originally used spindle motor has been replaced. “When selecting the optimal drive, we received outstanding technical support from Faulhaber”, emphasizes Frank Woodcock. As the Zippermast is often used under the most severe conditions, it must have a particularly robust and long-lasting motor. Furthermore, it was important to achieve very high performance at low volumes. “The motor which drives the guiding spindle, had to find space between two of the three coiled steel tapes and could only have at most a diameter of 32 millimeters”, recollects Andreas Eiler, who supervised the project at Faulhaber. Nevertheless, the DC-micromotor had to deliver high output torque in order to extend the mast quickly even when loaded. They therefore jointly decided to use a Faulhaber DC- micromotor. This provides a rated torque of 120 mNm with its powerful rare-earth magnets. The Zippermast also requires a very powerful drive. Here, the choice fell on a Faulhaber planetary gearhead. “They are made solely from steel components”, emphasizes Andreas Eiler. With this, the motor can also work reliably under the most adverse conditions and it has an extremely robust housing made from highly-resistant plastic. The DC-micromotor thereby fulfills the requirements for protection class IP68, keeps both dust as well as water away and is resistant to chemicals, UV and infrared radiation. The Faulhaber DC-micromotor also drives the seawater resistant variants of the Zippermast which can be integrated, for example, in a buoy in the sea. Woodcock even believes application in space is conceivable; he has already applied to participate on two projects. “For example, the Zippermast can be used as a boom for small and medium-sized satellites antennas or optical devices. In addition, we are working together with the company Odgargo who supply robot vehicles to the space agencies like NASA and CSA. We have just installed the Zippermast on one of the ‘Argo’ robots which may be used for a planned Mars mission. I figure we have a good chance to be involved in one of these space projects.” Photographs: Faulhaber GmbH & Co.KG MDA Technologies 4/2016