SBIR Phase I: Novel Chatter Control Strategy for Machine Tools

这个小型企业创新研究（SBIR）第一阶段项目将开发和实施一个全新的颤振控制方案。在许多机床中，流体轴承（也称为静压轴承和动压轴承）越来越受欢迎。该项目将采用低功率压电致动器来调节进入主轴外壳的流体的输入流量。通过仔细计算执行器电压，我们可以生成正确的输入流量，从而使颤振效应最小化。这种新方法有几个优点。首先，由于流体压力直接作用在主轴单元上，因此响应将是快速、直接和有效的。其次，由于压电是用来控制流量，而不是整个主轴外壳，只有非常低的功率放大器需要调节流量。第三，整体颤振控制成本将显著降低，因为可以使用商业现成的而不是定制设计的压电致动器。第四，不需要对机器进行重大修改，因为将在入口附近插入四个小型压电致动器。在机械设计上只需要做一个适度的改变，商业应用将为颤振控制提供一个实用的方法。颤振是机床金属去除率的主要限制因素。根据一阶近似，金属去除率为两倍的机床价值为两倍。这项技术将是有用的其他类型的机床，如铣削，车床和镗。

This Small Business Innovation Research (SBIR) Phase I project will develop and implement a completely novel chatter control scheme. In many machine tools, fluid bearings (also known as hydrostatic and hydrodynamic bearings) are gaining popularity. The project will apply low-power piezo actuators to modulate the input flow rate of the fluid into the spindle housing. By carefully computing the actuator voltages, we can generate the correct amount of input flow rate so that the chatter effects will be minimized. There are several advantages associated with this new approach. First, since the fluid pressure is directly acting on the spindle unit, the response will be fast, direct, and effective. Second, since piezo is used to control the flow rate, not the whole-spindle housing, only very low power amplifiers are needed to regulate the flow. Third, the overall chatter control cost will be significantly reduced as commercial off-the-shelf, rather than custom designed, piezo actuators can be used. Fourth, no significant modification of the machine is needed because four small piezo actuators will be inserted near the inlets. Only a modest change in mechanical design needs to be done.The commercial application will provide a practical approach to chatter control. Chatter is the primary limiting factor in metal removal rate in machine tools. To a first order approximation, a machine tool with twice the metal removal rate is worth twice as much. This technology will be useful for other types of machine tools such as milling, lathe, and boring.