Mid-Drive Motor For Robot Chassis

The mid-drive motor is a highly efficient power system mounted centrally on a robotic chassis. It transmits power to wheel assemblies or tracks via gearboxes, drive shafts, or chains, and is frequently employed in service robots, industrial AGVs, inspection robots, and off-road robots. Offering high torque, balanced centre of gravity, and extended endurance, it achieves energy efficiencies of up to 80-85%, making it well-suited for complex terrains and heavy-load applications.

High Torque Output and Terrain Adaptability: Delivering sustained peak torque of 50–120Nm, this system reduces transmission leverage effects through a centralised layout and employs a concentrated heat dissipation design. It reliably handles inclines of 15–30 degrees and heavy-duty tasks ranging from 50 to 200kg. In practical applications, such as outdoor inspection robots traversing gravel or muddy terrain, slip rates are significantly reduced.

Balanced weight distribution and dynamic stability: Motors are centrally mounted within the chassis, lowering the overall centre of gravity by 15-25%. This effectively mitigates the risk of lateral tilt caused by uneven loading from robotic arm operations or sensor payloads. Combined with low-inertia transmission design, this enhances postural stability during sharp turns, significantly reducing the probability of cargo overturning during logistics transport.

Redundancy and safety mechanisms: The integrated electromagnetic clutch automatically switches to low-resistance coasting mode during power failure, ensuring the chassis can be manually manoeuvred or seamlessly transitioned to auxiliary power in the event of malfunction.

Enhanced durability and environmental resilience: The motor housing is positioned away from direct wheel impact, reducing vibration loads by 60%. The IP54 protection rating has passed salt spray, dust, and sand exposure tests, along with temperature cycling tests from -20°C to 55°C.

Modular transmission and terrain compatibility: Seamlessly adapts to two-wheel differential, four-wheel drive, or tracked chassis via interchangeable gearbox/chain modules, supporting electronic differential steering and multi-speed gearing (e.g, 0-5km/h low-speed precision steering to 20km/h high-speed cruising).

Intelligent Integration and Dynamic Control: Native support for ROS 2, CAN FD, and EtherCAT industrial buses. Combined with an integrated high-precision torque sensor (±2% error), it enables real-time load sensing and dynamic power output adjustment. During autonomous navigation, torque feedback data is fused with SLAM algorithms, reducing path tracking error to ±1cm and enhancing mapping accuracy.

Mid-mounted motors serve as the power solution for robotic mobile platforms in complex operating conditions, owing to their high torque output, precise differential control, and low centre of gravity design.

Indoor industrial environments: such as warehouses, factories, or logistics centres, where they are employed in AGVs (Automated Guided Vehicles) for goods handling. The high energy efficiency and precise differential steering of mid-mounted motors are well-suited for prolonged operation on flat surfaces.

Outdoor Complex Terrain: Such as power line inspections, mines, or construction sites. Inspection robots (tracked or four-wheel chassis) utilise the mid-drive motor's high torque to navigate rugged terrain with gradients of 15-30°, muddy or gravel surfaces. Combined with IP65 protection, they withstand dust ingress and brief immersion.

Agricultural settings: For fields, orchards, or greenhouses, deployed in automated seeding, crop protection, or harvesting robots. Low-speed cruise mode maintains stability on wetlands and soft soil paths, while torque dynamic compensation technology navigates uneven field ridges to prevent bogging. Additionally, sealed bearing designs pass pesticide corrosion testing, ensuring sustained operational capability and equipment corrosion resistance in demanding field conditions.

Urban Service Environments: Such as hotels, hospitals, or shopping centres, for meal delivery, cleaning, or logistics robots. The motor's low centre of gravity and smooth acceleration suit flat floors or gentle slopes, providing quiet, reliable movement.

Research and Education Environments: Such as university laboratories or open-source robotics development platforms (ROS-based). Mid-mounted motors, favoured for their modular design and ease of integration (supporting ROS/CAN communication), are commonly used in indoor test benches or simulated terrain experiments.