Iterative springback compensation of NUMISHEET benchmark #1

Upon unloading after the forming stage, a sheet metal product will spring back due to internal stresses. Springback\ud is a major problem for process-planning engineers. In industrial practise, deformations due to springback are compensated\ud manually, by doing extensive measurements on prototype parts, and altering the tool geometry by hand. This is a time\ud consuming and costly operation. In this paper the application of two compensation algorithms, based on the finite element\ud simulation of the forming process are discussed. The smooth displacement adjustment (SDA) method and the springforward\ud (SF) method have been applied to several industrial products, such as the NUMISHEET 2005 benchmark#1. With the SDA\ud method successful compensations have been carried out. For the SF method some principal problems remain

Compensating springback in the automotive practice\ud using MASHAL

New materials are used in the automotive industry to reduce weight and to improve crash performance. These\ud materials feature a higher ratio of yield stress to elastic modulus leading to increased springback after tool release. The resulting\ud shape deviations and their efficient reduction is of major interest for the automotive industry nowadays. The usual strategies for\ud springback reduction can diminish springback to a certain amount only. In order to reduce the remaining shape deviation a\ud mathematical compensation algorithm is presented. The objective is to obtain the tool geometry such that the part springs back\ud into the right shape after releasing the tools.\ud In practice the process of compensation involves different tasks beginning with CAD construction of the part, planning the\ud drawing method and tool construction, FE-simulation, deep drawing at try-out stage and measurement of the manufactured part.\ud Thus the compensation can not be treated as an isolated task but as a process with various restrictions and requirements of\ud today’s automotive practice. For this reason a software prototype for compensation methods MASHAL – meaning program to\ud maintain accuracy (MASsHALtigkeit) – was developed. The basic idea of compensation with MASHAL is the transfer and\ud application of shape deviations between two different geometries on a third one. The developed algorithm allows for an effective\ud processing of these data, an approximation of springback and shape deviations and for a smooth extrapolation onto the tool\ud geometry.\ud Following topics are addressed: positioning of parts, global compensation and restriction of compensation to local areas,\ud damping of the compensation function in the blank holder domain, simulation and validation of springback and compensation of\ud CAD-data. The complete compensation procedure is illustrated on an industrial part

The impact of interview style on the development, maintenance, and transfer of rapport

Investigative interviews are a central part of policing. Police interviewers use the information obtained from interviews to develop investigative leads or to make effective decisions. Therefore, it is important that the information is as detailed and accurate as possible. The recognized importance of interviewing has resulted in substantial research efforts being placed into the development of techniques that enhance information provision. One proposal for how these techniques lead to greater information provision is via increased rapport between the interviewer and interviewee. Although numerous interviewing models recommend rapport, the impact of interview style on rapport has rarely been tested directly in interviews with suspects. There has also not been a consideration of how rapport would be affected by repeated exposure to specific individuals and law enforcement in general. In this thesis, I aim to test whether rapport once established can be maintained between multiple interviews and across multiple interviewers. This is a critical gap in our knowledge, as in police interviews it is common practice for suspects to be interviewed more than once and by different interviewers at different times. It is therefore important to know whether previous interactions with the police could affect future interactions in terms of rapport. A second key aim of this thesis is to test if nonverbal mimicry measured via motion capture suits can serve as an objectively rated behavioural proxy of rapport as several studies showed that behavioural mimicry is higher in people with well-established rapport and further, mimicry results in increased rapport. My findings suggest that the interview style impacts on rapport and mimicry. However, I could not find evidence for a link between rapport and disclosed information, or rapport and mimicry

Springback Compensation: Fundamental Topics and Practical Application

Now that the simulation of deep drawing processes has become more reliable the virtual\ud compensation of the forming tools has become reality. In literature, the Displacement Adjustment (DA)\ud algorithm has proved to be most effective. In this article it is shown how the compensation factor, required for\ud (one-step) DA depends on material, process and geometrical parameters. For this an analytical bar stretchbending\ud model was used. A compensation factor is not required when DA is applied iteratively and the\ud products geometrical accuracy is improved further. This was demonstrated on an industrial part. The\ud compensation varies over the product, leading to a reduction in shape deviation of 90% and more, a result that\ud could not have been achieved with one-step compensatio

The development of a finite elements based springback compensation tool for sheet metal products

Springback is a major problem in the deep drawing process. When the tools are released after the forming stage, the product springs back due to the action of internal stresses. In many cases the shape deviation is too large and springback compensation is needed: the tools of the deep drawing process are changed so, that the product becomes geometrically accurate after springback. In this paper, two different ways of geometric optimization are presented, the smooth displacement adjustment (SDA) method and the surface controlled overbending (SCO) method. Both methods use results from a finite elements deep drawing simulation for the optimization of the tool shape. The methods are demonstrated on an industrial product. The results are satisfactory, but it is shown that both methods still need to be improved and that the FE simulation needs to become more reliable to allow industrial application

Recent advances in industrially applied numerically aided springback compensation

Springback is a common and intrinsic phenomenon of every deep drawing operation. For\ud various reasons the application of high strength steels and aluminum in automotive industry is\ud still increasing. Unfortunately, these materials tend to larger springback than mild steels.\ud Therefore it is more difficult to guarantee the accuracy of the part shape without a proper\ud springback compensation. Several countermeasures can be applied to minimize springback, but\ud it is not always possible to reduce springback sufficiently. Additionally, the overbending\ud technique has been developed to counter springback by modification of the tool shape. This\ud method gives satisfactory results for a whole class of parts which are very susceptible to\ud springback. In this paper an improvement, the smooth displacement adjustment (SDA) method,\ud is presented. Basically the shape deviation of the part is calculated and subsequently\ud approximated by an L2-projection of sufficiently smooth global analytical functions. Due to the\ud restriction to analytical functions the computed shape deviations can be easily transferred to the\ud tool surface in order to compensate them. The use of the new method is demonstrated on an\ud industrial part. The paper ends with conclusions and recommendations

A Friend Who Does Me No Good: Aphorism in Matteo Ricci’s On Friendship

This paper argues that Italian Jesuit Matteo Ricci (1552-1610) designed his aphoristic compilation, Jiaoyou Lun 交友論–On Friendship (1595)–to serve the Jesuit mission of converting the Chinese to Catholicism and express the conflict he may have felt exploiting friends to forward the Jesuit mission. Utilizing friendships to allow for greater social influence was central to the Jesuit proselytization strategy in China. However, Ricci’s moral education from youth taught him to judge utilitarian friendships as immoral. The extant scholarship regarding Ricci’s On Friendship fails to acknowledge the significance of the aphoristic form to this work. To illuminate the value of aphorism to the Jesuit mission and this book, I analyze a selection of the book’s one-hundred maxims. My interpretation emphasizes the tone of authority and universality established through the genre’s concision. This brevity can raise questions about the meaning of the text and spark conversations, strengthening friendships among readers, and arguably furthering the goals of the mission. Additionally, the text’s inconsistent moral portrayal of utilitarian friendship may reveal Ricci’s ambivalence about his own friendships with Chinese literati. Through close reading of On Friendship, I posit that the aphorism\u27s brevity and ambiguity may have allowed Ricci to express his emotional unrest while still crafting a book that could be considered a tool of proselytization

Emerson, I am trying to live...the examined life - The Transcendentalist Poet Mary Oliver

Even after the poet’s passing in 2019, Mary Oliver’s poetry continues to soothe and inspire her readers. Celebrated for her mindful and meditative poetic responses to the natural world, her name has been linked to literary movements such as American Transcendentalism and Romanticism. This article traces such Transcendentalist thought in selected works by Mary Oliver through comparisons made to Emerson’s concept of the Over-Soul and the position of the poet as presented by both writers

The Effects of Videotape Relaxation Training and EMG Feedback on Frontalis Muscle Activity

Two studies were undertaken to assess the relative effects of videotape progressive relaxation and EMG feedback. During both studies EMG levels of the frontalis muscles were recorded. Ten subjects referred by the University Counseling Center, as high anxiety individuals, were exposed to one of the above two methods. A single subject multiple baseline design, including reversals, was used. Each subject was given four or six baseline sessions, one, four or seven exposures to the videotape and three return to baseline sessions. In the second study, using the same design, each subject was given four or six baseline sessions, four or seven EMG feedback sessions and four return to baseline sessions. No relaxation in frontalis EMG occurred during the initial baseline condition for any of the subjects in either study. Only those subjects given seven exposures to either relaxation training method produced significant decreases in frontalis EMG. The videotape subjects showed decreases during both the modeling and return to baseline conditions. The EMG feedback subjects produced systematic decreases in frontalis EMG during the feedback condition but increases occurred during the return to baseline condition. The clinical utility of both relaxation procedures might be increased by: increasing the number of training sessions, programming for generalization to real life situations, and developing other versions of the videotape relaxation program. The suitability of frontalis EMG as an overall indicator of body relaxation is questionable