Electric, hydraulic, and pneumatic are the three main motion technologies in drive systems. Which one you use depends on the characteristics of the application. Electric control excels when very precise or continuous movement is required. Electric servo control is useful in various applications, such as computer numerical control (CNC) of axes in machine centers or elevators. This type of control is frequently used in assembly operations. Hydraulics is the choice for high-load conditions when rapid response is required. It can withstand the highest pressure of the three motion types, up to 100 tons. Pneumatics ensures safety and reliability in adverse environments, being less sensitive to high and low temperatures, dust, mechanical vibration, humidity, and electronic noise. Hydraulics and pneumatics can easily achieve linear motion using various cylindrical devices. Electric control, being motor-driven and starting with rotary motion, requires devices to convert this rotary motion into linear motion, such as ball screws. The following key operating parameters can influence the choice of motion type: Accuracy and repeatability: Electric servo systems offer the highest level of accuracy. Modern hydraulic and pneumatic valves offer more powerful control than ever before, and are more effective at maintaining constant pressure, such as bearing a load at a designated location. Complexity: Hydraulic servo digital control is ideal for multi-axis applications. Electric servo control excels in synchronization, while pneumatics offers excellent performance and ease of use. Productivity: Improving system productivity relies on increasing output and reducing machine turnaround time. The actual operating speed of simple electric linear motion is 10 m/s, twice that of hydraulics and pneumatics. Lifecycle Cost: Cost is not a sole metric when evaluating any technology. However, a balance between acquisition cost and lifecycle cost is essential. About the Authors: – Rodney Rusk, Dan Warmus, Brian Rogers, and Thomas Dwyer are pneumatic, hydraulic, and electric experts at Bosch Rexroth. Visit www.boschrexroth-us.com.