Linear position sensors provide high accuracy steering for agricultural vehicle guidance systems
26 January 2016
Precision Decisions Ltd specialise in hardware and software solutions for agriculture that maximise yield potential through the use of Global Navigation Satellite System (GNSS) automatic vehicle guidance.
The Yorkshire based company are particularly strong in an area of agronomics known as controlled traffic farming (CTF) where satellite guidance is employed as a key element to reduce vehicle travel over the field to the very minimum. CTF essentially reduces overlaps and travelled ground in fields to provide farmers with significant benefits that include increased soil health, reduced tilling, seeding and fertilizer application costs, and overall increased efficiencies. For the highest precision systems, with accuracy to better than ±2cm, the GNSS is often complemented with additional ground-based signalling equipment which can be from field portable transmitters and receivers or via mobile telephone masts. Such systems also benefit from on-vehicle wheel-angle position sensors (WAS) that provide steering position information to a guidance ECU as part of the hands-free steering servo loop.
As an integral part of a newly developed high-accuracy CTF system that is easily adapted to a wide range of farming vehicles Precision Decisions has called upon Variohm EuroSensor to supply TX2 series potentiometric linear position sensors for wheel angle measurement. The highly durable IP67 rated linear sensor, from Variohm’s distribution partner Novotechnik, was selected as it offers many advantages over more traditionally specified rotary transducers that are externally mounted and require pushrods and associated linkages which contribute to increased backlash and linkage wear leading to inaccuracy and lost motion.
The compact TX2 is directly fixed to the steering arm using its backlash-free pivot head mountings without the need for additional linkages - and with a generous angle of free movement of up to +/- 12.5 degrees to compensate for misalignment, is easy to install and commission. With eight available standard measuring ranges from 25 mm to 300 mm, input voltage up to 42 VDC, independent linearity specification of 0.05% and positional repeatability to under 10 microns, the sensor provides the precision and the installation flexibility required to mechanically and electrically adapt to the steering systems of the widest possible range of vehicles.
In this application the TX2 is typically powered with 5 VDC to derive a 0...5 V output to a sophisticated PVED computer controlled hydraulic steering system which is capable of providing millimetre level accuracy.
The fully protected sensor is well suited for adverse environments where its use is aided with a double sealed actuating rod and metal mounting flanges for maximum protection against dirt, dust, oil and humidity.
The TX2 series has a rated life of more than 50 million movements and employs Novotechnik's unique conductive plastic resistance element technology and elastomer damped multi-fingered precious metal wipers to maintain complete contact under extreme shock conditions that are specified to 50g for 6 ms, with equally impressive vibration durability.
Precision Decisions’ After Sales Support Manager, David M. Hart, is very pleased with the performance of the TX2. “The accuracy and repeatability of vehicle position within the field is paramount in order to obtain correct machine placement for any operation, not least controlled traffic farming. Precision Decisions have chosen the Variohm EuroSensor TX2 linear transducer on the grounds of accuracy, robustness and simplicity of construction. It is also cost effective.” Hart continues his evaluation. “The unit has proven simple to fit to a broad range of tractors and has first class positional accuracy. On-line steering acquisition and position interpretation is rapid, smooth and without oscillation.”
Variohm EuroSensor is a designer, manufacturer, distributor and supply chain partner providing complete sales and application support across a comprehensive range of position, load, force and temperature sensor technologies - for demanding measurement applications across industry, construction, agriculture, motorsports, research and more.
Other Press Releases By This Company
- 19/08/2022 - Aplication Note: Gibson Technology choose Variohm EuroSensor D-shaft throttle position sensors for Le Mans 2022
- 16/08/2022 - Absolute Encoders
- 31/05/2022 - Potentiometer-based sensors offer impressive price vs. performance: Novotechnik’s well-proven LWH series linear position sensors gain from design optimisation
- 07/02/2022 - Positek’s displacement sensors comprehensively include ATEX, IECEx and UL intrinsically safe versions
- 05/10/2021 - Onboard truck and trailer weighing: Variohm supplies Zemic load cells to Onboard Solutions & Sons
- 08/09/2021 - New Novotechnik RFE-3200 angle sensor perfectly suits mobile machinery and off-highway position measurement
- 27/07/2021 - Variohm EuroSensor’s new ETP21R temperature sensor is spec’d for railway applications
- 08/06/2021 - Pressure sensing with functional safety for hydrogen processing and storage systems: Variohm’s SMO31H2 sensor now available in PL:d compliant version
- 25/05/2021 - Innovative virus-free air circulation module from Schulz-Berger works with DLTI-U.500 differential pressure sensors from Variohm
- 22/04/2021 - Mobile and heavy-duty machinery control: In-cylinder position sensor now with CANopen and CAN SAE J1939 interface options
- 07/04/2021 - Variohm EuroSensor’s comprehensive range of piezo resistive pressure transducers
- 21/09/2020 - Machine safety without SIL: Wachendorff’s WDG series redundant encoders provide cost-effective safety
- 14/09/2020 - Sensor Applications in Agricultural Machinery
- 19/07/2020 - Variohm Eurosensor launch new range of glass and epoxy coated NTC bead thermistors
- 12/06/2020 - Roll feed and winding web length measurement made easy: Wachendorff LMSMA length measurement systems optimise length, position and speed feedback
- 04/05/2020 - World Magnetics and Variohm work round the clock to fulfil increased demand for ventilator pressure switches
- 21/10/2019 - Novotechnik magnetic angle sensor range now with J1939 interface
- 13/09/2019 - Pressure switches selected for hydraulic systems safety monitoring on BOOM XB-1
- 13/09/2019 - Variohm EuroSensor’s Euro-CMRT micro threaded angle sensor
- 13/09/2019 - Pressure measurement for safety critical applications
- 13/09/2019 - Variohm EuroSensor launch new two-part puck and magnet programmable angle sensor
- 13/09/2019 - Specialist Ring Terminal Temperature Probes
- 13/09/2019 - Wide choice of custom options for new Hall Effect angle sensor range
- 13/09/2019 - Variohm Group expands with the acquisition of displacement sensor specialist Positek
- 13/09/2019 - Wiring harnesses include glass encapsulated thermistors
- 13/09/2019 - Active wheel speed sensing in compact and durable package
- 19/12/2018 - Dual redundant angle position sensing for safety critical tasks
- 19/12/2018 - New durable and compact pressure sensor offers wide measurement range and elevated temperature use
- 23/11/2016 - No batteries or gears: Contelec’s new absolute single-turn/multi-turn contactless sensor has improved design
- 07/11/2016 - Heavy duty rotary position feedback: Contelec Vert-X 48E non-contacting magnetic sensor suits extreme environment applications
- 20/09/2016 - Variohm EuroSensor adds puck and magnet option to Euro-X Hall Effect angle sensor range
- 12/09/2016 - Hexagonal bolt temperature probes provide ideal solution for Comlab multi-band receivers
- 09/08/2016 - Fast delivery for standard or bespoke strain gauges
- 25/04/2016 - Linear position sensors for professional mountain bike set-up: Variohm EuroSensor VLP and ELPM used by UCI Mountain Bike World Champion
- 12/04/2016 - Durable rotary position sensing: Novotechnik’s Hall-effect single- and multi-turn rotary sensors provide multiple options
- 31/03/2016 - Novotechnik RFC-4800 touchless technology angle sensor now with CANopen
- 08/03/2016 - VTP11 rotary sensor offers 8 mm D-shaft mounting and well-proven resistive element technology
- 22/02/2016 - Wachendorff industrial encoders are integrated in conveyor and web length measurement systems
- 16/02/2016 - Variohm EuroSensor adds intrinsically safe pressure and level switching and sensing components
- 19/01/2016 - Crucial evidence: DesignFlex pressure switches aid improved DNA sampling process
- 15/12/2015 - ZEMIC strain gauges added to Variohm EuroSensor product range
- 10/12/2015 - New high-specification temperature probe offers extended performance at competitive cost
- 23/11/2015 - Long travel linear position measurement: Variohm supply draw wire sensors to Hunger Hydraulics for lifting bridge application
- 09/11/2015 - Variohm EuroSensor adds 8 mm D-shaft option to motorsports-proven Hall Effect angle sensor range
- 03/11/2015 - Position sensors with 10m range: Variohm EuroSensor adds new Celesco SK series cable extension sensors
- 19/10/2015 - Pressure and temperature measurement combined: Variohm EuroSensor's EPTTE3100 provides a cost effective and space saving solution
- 12/08/2015 - Ginetta Cars upgrade dynamometer rig with Variohm EGT sensors
- 01/07/2015 - Improved sailing performance with DesignFlex enabled Sip-and-Puff
- 03/03/2015 - High precision single-/dual-axis inclinometer offers wide choice of options
- 12/02/2015 - Wachendorff revise and improve incremental encoder range
- 04/02/2015 - UN/ECE R10 electromagnetic compatibility for automotive and mobile vehicle sensors
- 07/01/2015 - Contactless angle sensor range adds multi-turn capability, with 16-bit resolution version available
- 26/11/2014 - Non-Contacting Sensor for Electro-Hydraulic Actuators
- 13/10/2014 - Variohm EuroSensor’s custom designed temperature probes meet SPA’s high quality standards
- 06/10/2014 - For Applications Where Safety Is A Concern: High-Precision Multiple Section Potentiometer for Industrial Use
- 06/10/2014 - Small, lightweight, gearless, and now also featuring digital interfaces: Advancement in gearless Multiturn Sensors
- 06/10/2014 - Variohm’s new 9660 Hall Effect rotary position sensor is ideal for harsh environment angle measurement
- 26/09/2014 - Multiple use of sensors: Garford’s Robocrop precision guided weed control equipment applies position, pressure and temperature sensor technologies from Variohm
- 30/06/2014 - Variohm announce new platinum thin film RTD sensor line
- 12/06/2014 - Variohm EuroSensor provide Novotechnik RFC series ‘touchless’ two-part sensor for the Big Bale Transtacker
- 25/03/2014 - Variohm EuroSensor launch new low-cost pressure sensor for OEM applications
- 06/03/2014 - Wachendorff adds CAN bus I/O node functionality to CANopen absolute encoder
- 16/01/2014 - Super-Flat Non-Contacting Rotary Sensor
- 13/01/2014 - Molten Rock choose Variohm for all-terrain wheelchair power steering position feedback
- 05/12/2013 - Southern Manufacturing Show 2014 MiniTec UK - Stand F50
- 05/12/2013 - Southern Manufacturing Show 2014 LG Motion Ltd - Stand F48
- 26/04/2012 - New boiler probe has integrated connector
- 26/04/2012 - It's about The Challenge – Variohm Holdings launch new website
- 26/04/2012 - Life Racing's fast paddle gearshift system benefits from reliable rotary position sensor
- 27/02/2012 - Variohm EuroSensor now offers Lifetime Warranty on popular Meggitt Wilcoxon Research vibration sensor range
- 02/02/2012 - Application Story
- 01/02/2012 - Variohm EuroSensor adds new triaxial accelerometer to vibration sensor range
- 04/01/2012 - Contactless measurement principles in the fast lane
- 04/01/2012 - ZEMIC high capacity BM24R load cell arrives with OIML approval for use in washdown and harsh environments
- 15/12/2009 - Cryostat temperature measurement is critical for Variohm EuroSensor
- 04/12/2009 - Cost optimised linear position sensors from Variohm have open housing and two part design
- 23/11/2009 - Novotechnik conductive plastic technology suits harsh environment applications at realistic pricing levels
- 27/10/2009 - Variohm non-contact angle sensors open new applications
- 22/06/2009 - Twenty20 Floodlights use Variohm Position Sensors
- 12/05/2009 - The use of optical encoders for high accuracy positioning of cranes
