CYCLOIDAL VS HARMONIC
Cycloidal and harmonic drives are both suitable for creating high ratio transmissions in small spaces. This makes them ideal for use in robotics and automation applications. Each have their benefits for specific scenarios and applications.
HARMONIC DRIVES
CYCLOIDAL DRIVES
What is a harmonic drive, and how does it work?
A harmonic drive, also known as a strain wave gear, is a compact and lightweight gear system that provides high precision and zero backlash. It consists of three main components: a wave generator, a flex spline, and a circular spline.
The wave generator is an elliptical cam fitted with a ball bearing, which deforms the flex spline—a thin, flexible gear. The flex spline meshes with the circular spline at two opposite points, creating a motion conversion that allows for high gear reduction in a small footprint. The flexibility of the spline allows for very high positioning accuracy, making harmonic drives particularly useful in robotics and aerospace applications.
What are the advantages of harmonic drives?
Harmonic drives provide several key advantages, making them ideal for specific high precision applications:
- Their unique design eliminates backlash, ensuring extremely precise motion
- Their compact and lightweight designs with high gear reductions are perfect for tight spaces
- The deformation based motion provides exceptionally smooth operation with minimal vibration
- Their precision makes them highly effective in applications such as robotics and aerospace engineering
- The thin walled flex spline allows for a lightweight yet strong design
What applications use harmonic drives?
Harmonic drives are ideal for applications requiring ultra precise motion, such as medical robotics, aerospace systems, and high precision manufacturing. They are widely used in robotic joints, satellite positioning systems, and camera stabilization equipment.
What is a cycloidal drive, and how does it work?
A cycloidal drive, also known as a cycloidal reducer, is a type of gear mechanism that provides high torque and precise motion control. It uses a unique mechanism where an eccentric bearing drives a cycloidal disk. This disk rotates and interacts with a set of rollers, converting the motion into an output shaft movement.
Cycloidal drives use a combination of rolling and sliding motion to achieve their speed reduction. This results in multiple points of contact between the moving parts, distributing the load more evenly and reducing wear. The design enables high shock load resistance and precision positioning, making cycloidal drives a preferred choice in applications requiring durability and accuracy.
What are the advantages of cycloidal drives?
Cycloidal drives offer several advantages, including:
- High torque capacity due to multiple contact points distributing the load
- Robust construction for enhanced durability and greater shock loading capacity, ideal for industrial applications
- High efficiency under varying loads
- Though generally larger than harmonic gears, cycloidal gears are compact in design with high gear reductions
- High positioning accuracy
What applications use cycloidal drives?
Cycloidal drives are best suited for industrial automation, robotics, conveyors, and heavy machinery where high torque and durability are required. They are commonly found in robotic arms, machine tools, and factory automation systems.
How to decide on which kind of drive to use?
Customers choose harmonic drives or cycloidal drives for their high precision, compact size, and excellent torque-to-weight ratios. Harmonic drives are ideal for applications requiring zero backlash, high positional accuracy, and smooth motion—commonly used in robotics, aerospace, and medical devices. Cycloidal drives are favored for their shock-load resistance, durability, high torque capacity, and ability to handle overhung loads, making them well-suited for automation, industrial machinery, and heavy-duty environments.
Ultimately, the choice between harmonic and cycloidal drives depends on the specific needs of the application—including precision, load capacity, size constraints, and budget. By carefully evaluating these factors, businesses can select the optimal drive system to maximize performance and cost efficiency.
Our team of experienced engineers is ready to assist you in selecting the optimal technology for your application.
Contact us today to discover a solution tailored to your specific requirements.
Cone Drive harmonic and cycloidal gearing options
Cone Drive provides a wide range of motion control gearing options for use in a wide variety of industries.
HARMONIC DRIVES
Cone Drive Harmonic Solutions® offers the ultimate in precision motion control technology. Our harmonic product range includes gearheads, component sets, gear motor actuators, stepper motor integrations and other custom solutions. Our harmonic gearing features low to zero backlash, provides high transmission accuracy and can support a high ratio reduction in a single stage with low inertia. The highly accurate, torque dense design makes harmonic gears a great solution for robotic and positioning applications.
CYCLOIDAL DRIVES
TwinSpin® and DriveSpin® cycloidal reducers are designed for high precision, torque density, and weight reduction. The G & GH series provide high tilting stiffness, low friction, and high torque overload capacity with a high precision output bearing. In addition the DS & DSH series provide rotary motion and transfer output torque with high radial-axial load capacity.