中文摘要：

针对结构刚度测试中的转角测量问题,提出了一种新的小转角测量方法。采用激光位移传感器测量待测物体的切向线位移值,再通过几何关系将其转换成转角值。建立了包含4个因素的误差数学模型,分析了±1°的测量范围内各误差因素分别对测量结果的影响,结果表明：光斑距刻线标志偏距Δl对误差的影响较大。应用本方法,针对一异形构件进行了扭转刚度测试,当Δl上下限为±1 mm时,测量误差在2%左右,验证了本方法的有效性和准确性。

英文摘要：

A new small rotation angle measurement method is proposed to solve rotation angle measurement problems during structural stiffness tests. The tangential displacement of object is measured by laser displacement sensor,and is converted to rotation angle values through geometry relationship. A mathematical model for error is established to analyze each error factors which have effects on measurement results. Within the measurement range of ±1°,measurement results affected by error factors are respectively studied,which drew the conclusion that the offset Δl between light spot and engraved lines mark has greater influence on errors. The torsional stiffness of a profiled member is tested as an application of this method when Δlis equal to ± 1 mm,measurement errors are about 2%,which verify validity and accuracy of this method.