⚡ Linear Actuator Force Calculator
Calculate linear actuator force output
Motor output torque
Lead screw pitch (distance per revolution)
Typical: 70-90% for lead screws, default 80%
How to Use This Calculator
Enter Motor Torque
Input the motor's output torque. This is typically found in motor specifications. Use N·m for metric or lb-in for imperial units. For actuators with gear reduction, use the output torque after the gearbox.
Enter Lead Screw Pitch
Enter the lead screw pitch, which is the linear distance the actuator moves per full rotation of the screw. Common values: 2-10 mm for metric, 0.08-0.4 inches for imperial. This is found in actuator or lead screw specifications.
Enter Efficiency
Input the mechanical efficiency as a percentage. Typical values: 70-90% for lead screws (depending on thread type and lubrication). Default is 80% for standard acme threads. Ball screws typically have 90%+ efficiency.
Calculate Force
Click "Calculate Force" to determine the linear force output. Results are displayed in both Newtons (metric) and pounds (imperial) for your convenience.
Formula
Force = (2π × Torque × Efficiency) / (Pitch × 100)
Where:
- Force = Linear force output (N or lbs)
- Torque = Motor torque (N·m or lb-in)
- Pitch = Lead screw pitch (mm or inches per revolution)
- Efficiency = Mechanical efficiency (as percentage)
- 2π = Constant for converting rotational to linear motion
Example Calculation:
For motor torque = 2.5 N·m, pitch = 5 mm, efficiency = 80%:
Force = (2π × 2.5 × 80) / (5 × 100)
Force = (1256.64) / 500
Force = 2,513 N (≈ 565 lbs)
For imperial: 22 lb-in torque, 0.2" pitch, 80% efficiency:
Force = (2π × 22 × 80) / (0.2 × 100) = 552.9 lbs
Note: This formula calculates the theoretical force output. Actual force may be lower due to friction, wear, and other losses. For critical applications, use manufacturer specifications and consider safety factors. The pitch must be in the same units as the torque conversion (mm for metric, inches for imperial).
About Linear Actuator Force Calculator
The Linear Actuator Force Calculator determines the linear force output of an actuator based on motor torque, lead screw pitch, and mechanical efficiency. Linear actuators convert rotational motion from a motor into linear (push/pull) motion using a lead screw or ball screw mechanism. Understanding the force output is crucial for selecting the right actuator for your application and ensuring it can handle the required load.
When to Use This Calculator
- Actuator Selection: Determine if an actuator provides sufficient force for your application
- System Design: Calculate force requirements when designing automated systems
- Performance Analysis: Verify actuator specifications and expected force output
- Load Calculations: Ensure actuators can handle required loads in lifting, pushing, or pulling applications
- Educational Purposes: Learn about linear actuators and force calculations
Why Use Our Calculator?
- ✅ Dual Units: Provides results in both Newtons (metric) and pounds (imperial)
- ✅ Efficiency Factor: Accounts for mechanical losses in the calculation
- ✅ Quick Calculation: Instantly determine force output
- ✅ Step-by-Step Display: Shows the complete calculation process
- ✅ Free Tool: No registration required, works on all devices
Understanding Linear Actuators
Linear actuators convert rotational motor torque into linear force through a lead screw or ball screw. The force output depends on the motor torque, the screw's pitch (how far it moves per rotation), and the mechanical efficiency of the system. Lower pitch screws (finer threads) provide more force but slower speed, while higher pitch screws provide faster speed but less force. This trade-off is fundamental to actuator design.
Common Applications
Automation Systems: Linear actuators are used in automated machinery, robotics, and manufacturing equipment for precise linear motion control and load positioning.
Lifting Applications: Electric linear actuators are commonly used for lifting tables, adjustable desks, vehicle tailgates, and other lifting mechanisms requiring controlled vertical motion.
Push/Pull Operations: Actuators provide controlled pushing and pulling forces in applications like door opening, gate operation, and mechanical actuation systems.
Tips for Best Results
- Use actual motor torque specifications from the motor datasheet
- For actuators with gearboxes, use the gearbox output torque, not the motor torque
- Lead screw pitch is typically measured in mm (metric) or inches (imperial) per revolution
- Account for efficiency losses - typical lead screws: 70-85%, ball screws: 90%+
- Consider safety factors (typically 1.5-2×) for critical applications
- Actual force may be lower due to friction, wear, and other mechanical losses
Frequently Asked Questions
What is lead screw pitch?
Lead screw pitch is the linear distance the actuator moves per full rotation of the screw. For example, a 5 mm pitch means the actuator extends or retracts 5 mm for each complete rotation. Finer pitch (smaller value) provides more force but slower speed. Coarser pitch (larger value) provides faster speed but less force.
How does efficiency affect force output?
Efficiency accounts for mechanical losses due to friction, thread engagement, and other factors. Higher efficiency means more of the motor's torque is converted to useful force. Lead screws typically have 70-85% efficiency, while ball screws can achieve 90%+ efficiency. Lower efficiency means you get less force output from the same motor torque.
What's the difference between lead screws and ball screws?
Lead screws use sliding friction between threads, resulting in lower efficiency (70-85%) but are more cost-effective and self-locking. Ball screws use rolling balls between threads, providing higher efficiency (90%+) and smoother operation but are more expensive and typically not self-locking. Ball screws are better for high-speed, high-efficiency applications.
Can I use this for actuators with gearboxes?
Yes, but use the torque output from the gearbox, not the motor torque. Gearboxes multiply torque, so if a motor produces 1 N·m and the gearbox has a 10:1 ratio, use 10 N·m as your input torque. The gearbox efficiency is typically already accounted for in the gearbox's rated output torque.
Why is my actual force lower than calculated?
Actual force can be lower due to: (1) Friction losses not fully accounted for in efficiency, (2) Wear and degradation over time, (3) Loading conditions affecting efficiency, (4) Backlash in the system, (5) Temperature effects. Always use manufacturer specifications for critical applications and apply appropriate safety factors.