Humanoid robots are poised to revolutionize a wide range of industries, driven by sophisticated neural networks that control their joints, limbs, and end effectors to deliver nearly human-like abilities. Yet, this rapid adoption wouldn’t be possible without high-performance motion components tailored to specific applications and operating conditions.
Key sectors embracing humanoid robots include healthcare, retail, hospitality, manufacturing, logistics, and material handling. Goldman Sachs projects that the humanoid robot market could generate as much as $38 billion in sales by 2035.
To select the ideal motion components and fine-tune them for a robot’s specific tasks and settings, it’s essential to consider several critical design factors.
Humanoid Applications Demand Accurate and Carefully Regulated Movement
While humanoid robots often require optimized mechanical components to operate effectively in their intended environments, it’s wise to first explore what off-the-shelf products can offer your motion system before investing in custom solutions.
Once you understand your specific needs, you can work with a motion component expert who has a track record of adapting standard products to meet complex application demands. Below are some typical motion elements found in humanoids, along with standard components—using IKO products as examples—that are well-suited for these roles:
Joint motion—hips, elbows, wrists: One of the most crucial components in humanoid robots is the crossed roller bearing (CRBs). Featuring rollers arranged at right angles between the inner and outer rings, CRBs support radial, thrust, and moment loads simultaneously. This design increases contact with the raceway, enabling robotic joints like elbows and hips to handle heavy loads with improved rotational accuracy and stability—all within a compact footprint. It’s common for a humanoid to contain between 14 and 20 CRBs to support various motion functions.
Precision Linear Guides for Dexterous Gripping and Handling
Linear motion rolling guides are available in a variety of sizes, making them ideal for different sections of a humanoid robot. For instance, grippers and end effectors that replicate finger-like motion must open and close with high accuracy to securely grasp and manipulate objects. These guides are essential for pick-and-place operations, as they enable robot fingers to apply the right amount of clamping force while remaining agile enough to handle objects delicately and without damage.
IKO’s ML Series, for example, features some of the smallest sizes in the industry, while the LWL series offers widths as narrow as 1 mm (0.03 in.). Many models incorporate a recirculating ball-bearing design to ensure smooth, precise, and controlled linear motion.
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Extended-Reach Linear Guides for Enhanced Mobility and Vision
IKO linear guides also come in both standard and extra-rigid long versions, which can be integrated into a robot’s torso, arms, or legs to enhance reach—for example, enabling access to high shelves. These same guides can be installed in the robot’s neck, allowing the head to tilt or rise to look over or around obstacles, improving environmental awareness.
Spherical plain bearings—also known as bushings—help stabilize humanoid limbs by supporting pivoting movements that mimic human motion. A common use is in the foot assembly, where a rod connects the heel to the baseplate. With spherical plain bearings, the feet and ankles can tilt, rotate, or shift forward and backward more naturally.
Grasping and rotating tasks: Cam followers are valuable in internal robotic mechanisms that involve components riding along a cam path. When mounted above a circular arc, they allow additional freedom of motion. IKO offers some of the smallest cam followers on the market, with stud diameters as small as 1.4 mm (0.05 in.). Their internal design efficiently supports thrust loads with minimal wear, ensuring long-lasting performance.
Enhancing Performance Requires Balancing Motion Trade-Offs
Since humanoid robots operate in human environments and handle standard items, off-the-shelf motion components may seem adequate. Once you’ve chosen a component, performance hinges on aligning it with your motion goals.
Improving performance often comes with design trade-offs that raise challenging questions. That’s why it’s vital to work with an expert supplier who can assess your needs and guide your choices. This partnership becomes especially important when your humanoid design targets include:
Motion control: Joints that need to pivot, rotate, turn, or oscillate require well-matched motion components. To replicate human-like movement, different actuators and joints must work in harmony with precise motion control. For example, consider the goal of achieving smooth and accurate rotation in a standard robotic joint.
While using two thin-section bearings may achieve this, it increases space requirements and cost. IKO crossed roller bearings (CRBs) offer a compact alternative by combining the functionality of two bearings into a single unit. The “X” pattern lets them handle axial, radial, and moment loads at once in a compact design. Optional customizations—such as extra flanges or tailored bolt patterns—can also streamline installation.
Self-Lubricating Components Help Keep Humanoid Robots Operating Continuously
As with any motion-based system, proper lubrication of bearings and related components is essential in humanoid robots. These robots must often repeat tasks thousands of times without wear, all within tight spaces.
IKO tackles this with C-Lube, a built-in lubrication system in many products like linear guides and cam followers. In linear guides, C-Lube delivers oil directly to the rolling elements without making contact with the track rail. This allows for maintenance-free operation for up to five years or 12,500 miles (over 20,000 kilometers), and often longer. By incorporating C-Lube, these components provide extended, maintenance-free reliability—keeping humanoid robots in continuous operation.
Adapting to the environment: In some applications, humanoids must operate in unique environments that require more than basic motion control. For example, a robot may need to access objects located on shelves too high or deep for a human. A skilled supplier can add extensions or modify designs to help robots exceed human reach and handle complex environments.
Reducing maintenance demands: Designing motion systems with minimal upkeep in mind is vital when robots are expected to perform repetitive actions over long durations. While sensors can detect wear, IKO designs components to be maintenance-free for their entire lifespan.
Tailored Components Enable Humanoid Robots to Achieve Full Freedom of Movement
Custom motion components are key to giving humanoid robots full mobility and optimal performance across tasks. When designing custom solutions with CRBs—often used in up to 24 spots per humanoid—keep these best practices in mind:
Prioritize motion accuracy: As with stationary robots, precise movement is critical in humanoids. CRBs are engineered for high rigidity and positioning accuracy. Applying a light preload or reducing clearance boosts precision, eliminates backlash, and ensures smoother motion.
Reduce power usage: Lower energy consumption extends battery life. Custom CRBs can be optimized to distribute loads efficiently, reduce rotational torque, minimize friction with separators, eliminate backlash, or be manufactured from lightweight materials—all of which help decrease power demands.
Simplify installation and alignment: Since CRBs are responsible for enabling joint pivoting, proper mounting is vital to maintain accuracy and prevent misalignment or premature wear. Customization options—like special housings, flanges, plates, or tailored mounting holes—can streamline assembly and enhance durability.
Design for tough environments: While Alloy 52100 offers strength and fatigue resistance for most conditions, some humanoids will operate in demanding settings that require corrosion-resistant materials or protective features. Stainless steel, advanced seals, or coatings like black or thin dense chrome protect against dust, moisture, and grease leaks.
Plan for maintenance—or eliminate it: In applications where traditional grease lubrication isn’t feasible, IKO offers alternatives like dry film lubricants or liquid crystal lubricants for clean environments, ensuring reduced friction and long-term performance without the need for routine maintenance.
Engage Your Motion Component Supplier Early in the Design Process
Involve your supplier early when specifying custom components to avoid later complications or redesigns. IKO uses its expertise in CRBs, linear systems, bushings, and cam followers to deliver solutions for any humanoid application.
We collaborate closely with customers throughout the entire development process—from initial concept to testing and validation—to ensure the custom components perform reliably in real-world applications. Whether your robot is built for manufacturing, caregiving, household tasks, or order fulfillment, IKO is committed to helping you develop motion solutions that deliver dependable, long-lasting performance.
Read the original article on: The Robot Report
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