PD结合输入整形抑制单模态弹性机构振动仿真研究

Simulation Research on PD Combined with Input-shaping for Suppressing the Vibration of Single-mode Flexible Mechanical Structures

小阻尼单模态弹性机构的动力学特性表现为长时间减幅振动特性,如果仅仅考虑时域性能指标和频域性能指标设计PID控制器对其进行控制,可能导致系统过大的超调量和长时间的残留振动。为有效解决这一问题,将输入整形引入PD反馈控制系统中,提出PD结合输入整形控制策略。研究在4种典型输入信号作用下PD结合输入整形控制系统响应和控制力的通用表达式,定量分析输入整形对系统响应、控制力和能耗的作用规律。在相同反馈增益的情况下与PD反馈控制相比较,PD结合输入整形控制使系统产生较小的超调量,需要较小的控制力,允许系统具有较大的振动频率和较小的阻尼比,从而提高了系统的响应速度,而且输入整形有效地抑制系统的残留振动,从而减小系统的稳定时间,降低系统的能耗。通过仿真进一步证明了这一控制策略的有效性。

The mechanical structures that belong to a single-flexible mode with a slight damping behave the dynamical performance of long-time damped vibration.A PID controller to control mechanical systems,only designed on the criteria in time domain and frequency domain,may lead to excessive over-shoot and long-time residual vibration.To suppress effectively the residual vibration,input shaping is used in the PD feedback control system.PD combined with input-shaping control is presented for single-mode flexible mechanical structures.The system responses and the actuator efforts of PD combined with input-shaping control system,subject to four typical inputs,are described in general formula.The effect of input shaping on the actuator effort and energy consumption is analyzed quantitatively.Given the condition of the same feedback gains as PD feedback control,compared with PD control,PD combined with input shaping control produces smaller over-shoot and requires less actuator effort,and allows larger vibratory frequency and smaller damping ratio,thus improving the system response speed.Moreover,input shaping suppresses effectively the residual vibration,thereby reducing the settling time and energy consumption of the system.Simulation results show the validity of the control strategy.