Built-in Encoder for Precise Motion Applications

Bodine 33A motor delivers precise control for GPS-guided agricultural steering

The farm ensured the systems were fully integrated so that it does not lose out on any aspect for efficiency, but even a lack of such integration leaves many operations at high tech events like the National Farm Machinery Show. Among them are tractors, combines and other farm vehicles controlled through a steering system guided by GPS. Those include partial-assist steering to fully autonomous systems (including unmanned tractors pulling wagons behind a combine).

The Challenge: Reliable Motor and Encoder for Rugged Agricultural Use

Project:Assisted Steering for a Farm Vehicle OEM:Bodine Electric Company An OEM was developing an assisted steering solution for farm vehicles. The contraption featured a 12-volt DC motor, connected directly to the tractor’s battery, that used a spring-loaded roller wheel against the steering wheel.

In order to be in sync with the GPS servo controller, the motor required an encoder that could keep track of its shaft’s position for accurate steering input. As the application would be in a harsh industrial outdoor environment with difficult conditions, we were looking for a durable extended service life.

Bodine’s Engineering Solution

Bodine engineering reviewed several encoder options and recommended a magnetic 2-channel encoder with Hall sensors. This design provided for a resolution of 30 pulses per revolution, giving us the appropriate resolution between sensitivity and ruggedness.

For maximum protection in harsh agricultural operations, the encoder was housed inside the motor’s metal frame to protect against dust, moisture and vibration. For even greater dependability, Bodine also built in EMI (electromagnetic interference) suppression for consistent operation with GPS and other delicate control electronics.

Proven Longevity in the Field

The ultimate solution became the 33A-frame DC motor from Bodine, which was designed for low voltage (12 VDC) operation. With the encoder integrated and a protective housing, the result was an iron-clad (with accurate counting) and low-maintenance motor solution to provide farmers with a robust, accurate steering aid.

Field-proven through over nine years of uninterrupted production and field use, we have the highest confidence in the robustness of this workhorse motor and encoder system to meet even our most rigorous standards.

Advantages of the Bodine Encoder Motor Solution

• Integrated encoder ensures precise position feedback for GPS-guided systems
• 12V DC motor operates directly from tractor battery power
• Sealed, rugged construction withstands vibration and harsh outdoor environments
• Magnetic 2-channel encoder with Hall sensors provides accurate shaft resolution
• Proven long-term durability, still in production after nearly a decade

A Solid History of Success in Precision Agriculture

Traction Tires; Bodine’s technology in DC motors with integral encoders is still propelling precision agriculture forward, from auto-steering solutions to completely automated farm equipment. With precise control and solid reliability, Bodine gearmotors help farmers increase efficiency, minimize fatigue and stay on track—literally.