The coordinated design of the servo and the mechanical transmission system is crucial for eliminating vibration coupling and improving system dynamic performance. This requires a comprehensive approach encompassing mechanical structure optimization, control algorithm adjustment, parameter matching, and information exchange. The stiffness design of the mechanical transmission system is fundamental to vibration suppression. Insufficient stiffness in transmission components (such as couplings, gears, and lead screws) can easily lead to elastic deformation and torsional vibration when the motor outputs torque. For example, misaligned couplings or poor gear meshing can cause localized stress concentration, triggering periodic vibrations; while lead screw lead errors or axial clearances can exacerbate axial vibrations. Therefore, optimizing the geometry, material selection, and machining accuracy of transmission components is necessary to improve overall stiffness and reduce vibration energy transmission.
The output characteristics of the servo must be strictly matched with the load inertia of the transmission system. If the load inertia is significantly greater than the motor rotor inertia, the system response will lag, leading to overshoot during motor acceleration and drag during deceleration, resulting in oscillations. Conversely, if the load inertia is too small, the motor output torque may exceed the transmission system's tolerance, causing mechanical shock. In collaborative design, the equivalent inertia of the load referred to the motor shaft must be calculated based on the motor's rated torque, speed range, and transmission ratio to ensure the inertia ratio is controlled within a reasonable range (generally recommended to be less than 5:1) to avoid vibration coupling caused by inertia mismatch.
Optimization of the control algorithm is key to eliminating vibration coupling. Traditional PID control is prone to insufficient dynamic response due to fixed parameters, while model predictive control (MPC) or adaptive control can compensate for the nonlinear characteristics of the transmission system by adjusting gain parameters in real time. For example, introducing a transmission system lag compensation term in the speed loop control allows the motor output to "predict" the transmission system's response delay in advance, reducing overshoot error; or using an adaptive algorithm to dynamically identify load changes and adjust torque output to avoid vibration caused by friction or sudden changes in inertia. Furthermore, notch filters can suppress specific resonant frequencies by superimposing a reverse vibration signal in the control loop to cancel mechanical resonance.
Collaborative design of mechanical structure and control algorithm must be implemented throughout the entire system lifecycle. During the equipment design phase, transmission system parameters must be matched according to the servo's output characteristics to avoid unreasonable combinations such as "large motor with weak transmission" or "small motor with heavy load." For example, the equivalent inertia of the load can be reduced by adding a speed reducer, or installation errors can be reduced by selecting a high-rigidity coupling. Simultaneously, simulation analysis (such as finite element analysis) is needed to predict system vibration modes, optimize structural layout, and avoid the resonant frequency coinciding with the operating frequency. During operation, sensors must collect the transmission system's status (such as vibration and temperature) in real time and feed the data back to the motor control system, forming a closed loop of "sensing-decision-execution," dynamically adjusting control parameters to adapt to changes in operating conditions.
Vibration suppression also requires attention to the detailed design of the transmission system. For example, gear modification can reduce meshing impact, lowering noise and vibration; adjusting the preload of the lead screw can eliminate axial clearance and improve transmission accuracy; the elastic elements of the coupling can absorb some vibration energy, avoiding vibration transmission caused by rigid connections. Furthermore, the choice of lubrication method (such as grease lubrication or oil mist lubrication) also affects the friction characteristics of transmission components, thus affecting vibration levels.
Real-time information interaction is essential for collaborative design. Data transmission between the servo and the transmission system must have high bandwidth and low latency characteristics to ensure that control commands can respond promptly to changes in mechanical state. For example, high-speed communication between the motor controller and the sensors in the transmission system can be achieved through real-time industrial Ethernet protocols such as EtherCAT or SERCOS, avoiding control failures due to data lag. Simultaneously, interference-resistant processing of the transmitted signals is necessary (e.g., adding magnetic rings or using shielded cables) to prevent malfunctions caused by electromagnetic noise interference.
The collaborative design of the servo and mechanical transmission system must be based on the vibration coupling mechanism. Through multi-dimensional collaboration including mechanical structure optimization, control algorithm adjustment, parameter matching, and information exchange, a dynamic balance between power output and load demand can be achieved. This process requires not only theoretical analysis and simulation verification but also continuous optimization through actual testing, ultimately forming a highly stable and high-precision mechatronic system that meets the high-performance motion control requirements of intelligent equipment.
