The bipolar technique is a flaking strategy that has been identified from 3.3 Ma until the twentieth century, with no geographical or chronological homogeneous distribution. It is represented by the intentional contact of an active percussive element against a core rested on an anvil. This tool composite has been described by some researchers as a sign of low-skill of hominins, unable to perform successfully free-hand flaking or for flaking low-quality raw materials. Based on this premise, our research focused on the following question: Are there any quantitative and qualitative differences in terms of both kinematic parameters and technical skills between knappers with different levels of expertise when flaking using the bipolar technique? To get an answer, we developed a systematic experimental program with 12 volunteer participants with different levels of expertise. Then, to assess potential quantifiable differences and to understand the mechanics of bipolar technology, we did a video motion analysis based on kinematic parameters (including position, velocity, acceleration, and kinetic energy of the hammerstone). In addition, we performed a technological analysis of the experimental lithic assemblages to assess the technological differences between knappers based on their levels of expertise. In kinematic parameters, both statistical analysis and observations from the experiment clearly show that there are differences between the levels of expertise in this technique. Intermediate knappers have been observed to apply more velocity and kinetic energy than experts and novices. Also, differences were observed in the flaking strategies. Expert knappers show a longer reduction sequence, while intermediates show shorter one. Moreover, some of the novice knappers did not even obtain a single flake. The results of our experiment stress the complexity of bipolar flaking and that previous assumptions about it might be reconsidered, especially in terms of reconsidering the negative connotations attributed to this flaking technique.

双极技术是一种从 3.3 Ma 到 20 世纪已被识别的剥落策略，没有地理或时间上的均匀分布。它表现为主动撞击元件与放置在砧座上的核心的有意接触。一些研究人员将这种工具复合材料描述为古人类技能低下的标志，无法成功徒手剥片或剥片低质量原材料。基于这个前提，我们的研究主要集中在以下问题：不同专业水平的破碎工在使用双极技术剥片时，在运动学参数和技术技能方面是否存在定量和定性的差异？为了找到答案，我们开发了一个系统的实验计划，由 12 名具有不同专业水平的志愿者参加。然后，为了评估潜在的可量化差异并了解双极技术的力学原理，我们根据运动学参数（包括锤石的位置、速度、加速度和动能）进行了视频运动分析。此外，我们对实验石器组合进行了技术分析，以根据碎石者的专业水平评估他们之间的技术差异。在运动学参数方面，统计分析和实验观察都清楚地表明，该技术的专业水平之间存在差异。据观察，中级敲击者比专家和新手应用更多的速度和动能。此外，在剥片策略中也观察到差异。专业粉碎机显示出较长的还原序列，而中间人显示出较短的还原序列。而且，有的新手砍伐者连一块碎片都没有得到。我们的实验结果强调了双极剥落的复杂性，并且之前关于它的假设可能会被重新考虑，特别是在重新考虑归因于这种剥落技术的负面含义方面。