Important harvest workers: Certified safety sensors

Agricultural machines known as “precision farming” are highly technical products. Cultivation and harvesting processes can now be much more precise, efficient, and cost-effective than in the past. They also become more environmentally friendly and conserve resources, because the substances used are applied more precisely and in smaller doses. Losses are minimised. This requires a whole bundle of reliable sensors, which TWK has in its portfolio: for the positional alignment of tools or for speed measurement. This is robust sensor technology with a high IP protection rating of up to IP69K and high EMC resistance to meet the requirements in the field of any work process and suitable for any weather.

In addition, autonomous agricultural technology is increasingly being used, even in smaller vehicles for automated field maintenance – keyword field robots. With the digitalisation of agriculture as part of Industry 4.0, a high degree of functional safety in accordance with the IEC61508 and ISO13849 standards is important. TWK has developed a range of compact and robust encoders for this area. A wide range of interfaces and designs make it possible to find the right rotary and linear encoder or inclination sensor: PROFIsafe, Safety over EtherCAT or CANopen Safety in designs from 38 mm diameter. Because TWK takes its customers‘ needs seriously, additional requirements and interfaces can be quickly implemented and offered – these include J1939 Safety or LoRaWAN.

A few examples: For detection of the steering angle in a steer-by-wire system, compact encoders are available in 38- or 42-mm diameter, depending on whether singleturn or multiturn is required. They can be mounted in virtually any position. Where axial space is limited, the 30 mm housing depth version can be used. Even more compact is the new low-cost SIL2 safety encoder without shaft bearing, with CANopen safety interface and electronic multiturn detection. With a depth of only 20 mm, it is ideal for integration into existing systems. The actuating magnet is fixed to the moving application side and positioned opposite the encoder housing with no mechanical connection. These sensors can also be used for precise speed detection as they have a configurable speed signal.

For a smooth operation, it is usually necessary to keep the vehicle level, especially on uneven ground. TWK’s MEMS-based tilt sensors provide dynamic measurement and output an accurate tilt angle even in the presence of shock and vibration. A related device, the vibration sensor, can trigger an alarm via its digital output signal or a safety relay in the event of excessive vibration.

The units are available SIL2- or SIL3- and also PLd-certified or fully redundant. They can be supplied in aluminum or stainless steel 1.4404 housings. Other ratings such as UL® and ATEX or ASIL D are available. A wide range of flange and shaft styles, as well as optional plug or cable connections, ensure precise integration.

More information about the products is available at: https://shorturl.at/FQR04