xTS – Mechanical Testing System In X-ray Tomography Imaging System

X射线断层图像系统的原位加载系统

直接驱动滚柱丝杠还有另一个重要的优点，相较于采用齿轮箱或皮带传动装置的加载框架，没有引入额外的弯矩，而这些力会导致框架的扭曲变形，会使样品从初始加载平面偏离。 而Psylotech的xTS没有变速箱， 它通过直接驱动消除了这种扭曲力。

The direct drive roller screw has another substantial advantage. Alternative frames implement gear boxes or belt drive transmissions, introducing extraneous out of plane forces. These forces twist and contort the frame, moving samples away from the initial loading plane. Psylotech’s xTS has no gearbox. Its direct drive eliminates such twisting forces.

与其他系统相比，直接驱动伺服还具有相当的速度优势，因此每次断层扫描可以在更短的时间内完成。此外，样本旋转的测量直接来自用于伺服反馈的26位编码器。26位分辨率意味着xTS可以旋转0.0000054度。

The direct drive servo also enables substantial speed compared to other systems, so each tomography scan can be completed in less time. Moreover, specimen rotation is measured directly with the same 26-bit encoder used for servo feedback. The 26-bit resolution means the xTS can resolve 0.0000054 degrees in rotation.

除了可以施加轴向载荷，xTS还具有扭转试验能力。同样的，扭转伺服执行器通过零齿隙的谐波驱动，而不会产生额外的扭转力。这些伺服系统控制丝杠的旋转，丝杠按比例从属于螺母，以控制位移和角度位置。高刚性的结构和直接驱动载荷系减少了转角测量的误差。

In addition to axial loading, the xTS implements torsion capabilities. Again, the torsion servo actuator implements a zero backlash harmonic drive that does not cause extraneous twisting forces. These servos control the rotation of the screw, which is ratiometrically slaved to the nut to control displacement and angular position. The rigid, direct drive load train reduces error between measurement and angle at the grip.

最后，xTS还可以配置环境腔。该环境腔前后各有一个窗口，以允许X射线通过。为使内部体积最小化，可将该室旋转90度，以容纳轴向或梁弯曲样品。减小体积可提高效率、简化控制并提高温度均匀性。

Finally, the xTS can be configured with a temperature chamber. The chamber would have a window  in front and back to allow x-ray pass through. To minimize internal volume, this chamber can be rotated 90 degrees in order to accommodate axial or beam bending samples. Minimizing volume improves efficiency, simplifies control and improves temperature uniformity.

总之，Psylotech的xTS通过对称性设计、精密的加工品质和直接驱动作动器的组合，独特地控制了样品在测试过程的离面运动。因为数字体相关的分辨率可以小到2微米，所以控制离面运动对于X射线断层成像非常重要。xTS还提供26位的角度分辨率并保有未来增加环境腔的扩展潜力。

In summary, Psylotech’s xTS uniquely controls out-of-plane motion though a combination of symmetry, precision machining and a direct drive actuator. Controlling out-of-plane motion is important for x-ray tomography, because digital volume correlation resolution can be as small as 2 microns. The xTS also offers 26-bit angular position resolution and future expansion potential with an environmental chamber.

Specifications

*minimum value, longer strokes available at expense of system height

**higher speeds available at expense of force capacity

***minimum value, system height easily increased

xTS在美国实验力学学会 SEM 2020年会上的介绍