Roller coaster tech: HeavyDuty encoders deliver reliable speed data
In Europe's biggest roller coaster, the Helix, POG 10 HeavyDuty incremental encoders from Baumer monitor the speed of the carriage's drive as it approaches the start ramp. The HeavyDuty technology guarantees high reliability and precision under extreme environmental conditions at the Liseberg amusement park in Gothenburg, Sweden -- serving up thrills and reassuring safety for riders.
Liseberg is Sweden's largest amusement park. The Helix roller coaster is one of the attractions that revs up an adrenalin kick. With a 1,380-m track, Helix is the longest looping roller coaster in Europe and the second longest in the world. It hurls its riders at up to 90 km/h through six loops and exposes them to up to five times their own bodyweight. This is the first time anywhere in the world where half of the riders (Helix takes up to 28) sit facing backwards, making the ride even more exciting.
Thanks to an ingenious combination of labyrinth and shaft seals, Baumer HeavyDuty encoders are permanently protected against contamination.
Before the start, the riders have to be brought to the start ramp at a height of 41 m. Controlled asynchronous drives with 315 kW of power are used to move the carriages into the start position. The speed of this drive is recorded by the original Hübner Berlin POG 10 HeavyDuty encoder from Baumer. This is no easy task, because the roller coaster is freely exposed to the elements -- heat from the sun, moisture from rain, and/or wind.
The POG 10 incremental HeavyDuty encoder and its sister model, the HOG 10 with hollow shaft, are among the most versatile product ranges of the Baumer HeavyDuty encoders. They deliver reliable speed data in a host of applications and operate under the toughest conditions. As a result, they help prevent failures and maintain the availability of machines and systems. This saves downtime costs in a host of applications. With the roller coaster, it even makes a valuable contribution to the safety of human life -- a malfunction in the drive of a carriage would at best be annoying for the riders, and at worst a life-threatening experience.
Baumer HeavyDuty encoders feature bearings at both encoder shaft ends for incredible power reserves and an unrivaled service life. Due to its outstanding resilience to axial and radial forces, the arrangement with bearings at both encoder shaft ends has proven its worth in the construction of many different types of electrical machines.
The HeavyDuty technology of the POG 10 guarantees high reliability under challenging environmental conditions through numerous specific features. Thanks to solid and generously dimensioned wall thicknesses and a warp-resistant design, the die-cast housings are extremely robust and highly resistant to vibration and shock. Bearings at both encoder shaft ends and the metallic incremental disk offer huge power reserves and unparalleled durability through extreme resilience to axial and radial forces. For outdoor use (in this roller coaster application, for example), the excellent anticorrosive properties of the CX category of HeavyDuty encoders to EN ISO 12944, achieved through an optimal choice of material and high-resistant coating, are also extremely important. These properties allow the encoders to be used even on or in the ocean, in the Arctic, in the tropics, or in the desert.
Hübner Berlin HeavyDuty encoders in the HOG 10 and POG 10 series offer the highest possible availability, an unmatched service life, and fail-safety in any environment.
The combination of labyrinth and shaft seals also protects the inner workings of the HeavyDuty encoders from solid, moist, and paste-like contamination. This sealing concept conforms to protection classes IP 66 and IP 67 within a broad temperature range up to 95 C. Current-insulated bearings protect the ball bearings of the encoder from current flashovers, and this averts any impairment of the lubricant effect. The result is an almost indestructible full package that effectively prevents potential malfunctions and failures, even during tough, continuous use in a roller coaster. This is all the more important because a replacement can get very costly -- not because the encoder itself is expensive, but because it is typically mounted in hard-to-access accessible locations, as is the case on a roller coaster.
Reliable precision is ensured by the interference-immune scanning function with highly robust, optical circuits (Opto-ASIC). This guarantees optimum electromagnetic compatibility with a burst strength for high-voltage pulses of up to 4 kV. In addition, the Enhanced Monitoring System (EMS) continuously checks numerous encoder functions, swiftly detects connection and encoder errors, and transmits the encoder status to the inverter or to the control via an error output.
The HeavyDuty encoders achieve the best possible SinCos signal quality through the LowHarmonics technology for outstanding control quality, low drive heat-up, and high energy efficiency. The incremental square signal outputs also have short-circuit-proof powerful transistor drivers for peak currents up to 300 mA. They ensure reliable signal quality even over long-distance transmissions up to 350 m.
These features -- resilience and precision -- make an important contribution to ensuring that the Liseberg roller coaster riders are brought to the start ramp safely and at the correct speed. It's a good thing too, since this ascent to 41 m is thrilling enough without any failures.
When is an encoder "HeavyDuty"?
"HeavyDuty" is neither a protected brand nor the name of a standard. The HOG 10/POG 10 product range of Baumer Hübner, however, has generally been considered the defining "original" for 25 years. The features that set this range apart and against which the segment is benchmarked are:
Mechanical resilience: resistance to hard shocks, vibration, and forces on the rotary shaft for many years;
Impermeability: sealed against dirt, dust, and moisture;
Electrical resilience: electronic components inside the encoder are shielded against electromagnetic fields and powerful output drivers; and
Precision: reliable signal delivery, allowing a precise open-loop and closed-loop control of drives and generators.
Baumer says it considers "HeavyDuty" to be an all-encompassing performance promise. It guarantees that an encoder will function reliably and precisely at all times over a prolonged period and under adverse conditions.
VIDEO: Helix ride drone view. [Credits:
Learn more about the Incremental HeavyDuty encoders HOG 10/POG 10 here.