In these situations, high-performance sensor technology is essential for safe operation. The steering angle, wheel speed, and vehicle position must be reliably available at all times.
Small, lightweight safety sensors are necessary to save space and weight in agile and compact systems. TWK offers a range of certified, compact sensors with various safety interfaces, such as single-turn encoders with a housing diameter and length of only 38 mm and a fail-safe interface via EtherCAT (FSoE) (TRK38), or devices with a housing length of only 30 mm and a CANopen safety interface with a diameter of 55 mm (TBN55). Different housing designs are available for these and other safety interfaces, such as PROFIsafe via PROFINET. Sensors with our reliable multi-turn gear are also available starting at 42 mm in diameter. SIL2 absolute encoder with fail-safe interface via EtherCAT. These miniature encoders can be mounted on the wheels of an automated guided vehicle to detect vehicle speed. Optionally, they can be mounted on the vehicle's drive motor. The devices are also available with magnetically shielded stainless steel housings.
They can handle speeds up to 15,000 rpm and have a typical position resolution of 16 bits/360°. Another application for compact encoders is detecting the vehicle's steering angle. Here, measurements can be taken at the wheels or, after an intermediate transmission point, at the servo motor. In the latter case, TWK offers devices with SIL2-certified software, a feature known as the "rotation ring," which reliably translates the motor/sensor shaft position into the wheel position (steering angle). This works for arbitrary rotations across the entire measurement range and for at least 1024 revolutions, even when the encoder is switched off. The wheel position is reliably and accurately indicated when the encoder is switched back on. During commissioning, the user inputs the required gear ratio and resolution as parameters via the encoder interface, and the encoder is then ready for use. All devices are certified according to IEC 61508 and/or ISO 13849, at SIL2 or PLd level. Additional devices with SIL3 certification are also available. TWK also offers UL®, E1, ATEX/IECEx, and fully redundant (R2) certified sensors.
