First of all, our bionics experts took a close look at the fins of the manta ray. Although this creature lives in water, its large pectoral fins beat up and down like wings when it swims. We transferred this principle to the Air_ray in 2007. The flow-optimised design of the artificial ray increases aerodynamic efficiency, while the active torsion of the wings ensures that their full force is used. A servo motor pulls alternately on the two flanks in a lengthwise direction and thus moves the wings up and down. With an additional servo drive, the beating wing can be rotated around its transverse axis, so that the Air_ray can also be manoeuvred backwards. Thanks to its lightweight design, the uplift provided by helium and its beating wing drive with Fin Ray Effect®, it moves through the air just its natural role model moves through the water.

A similar concept is also behind the AirPenguins developed in 2009. Their flying technology is very close to the swimming technique of their biological models. The passively twisting wings allow both forward and reverse thrust to be generated.

The AirPenguins are the third group to fly autonomously and float within a defined airspace, which is detected by ultrasound transmitting stations. The penguins can move freely within this space.

A microcontroller gives it the opportunity to explore this space autonomously or according to specific rules.

从水下延伸到天空

2011 年,我们在此基础上解码了鸟类飞行的秘密,并研发出了 SmartBird。该仿生设计受银鸥的启发,无需外力驱动即可进行自主启动、飞行和降落。

其翅膀不仅可以上下拍打,而且能以特定方式扭转。该设计中有一个活动的关节扭转驱动装置,可通过一系列复杂原理实现前所未有的高效驱动。通过连续诊断确保安全飞行。SmartBird 飞行时,翅膀位置、翅膀扭转情况或电池状态等数据均由软件记录下来和实时验证。

蜻蜓的飞行技巧

蜻蜓的飞行方式更为复杂。其飞行特性十分独特:它可以沿所有空间方向飞行、在空中保持静止且缓缓滑翔而完全不用拍打翅膀。蜻蜓的两对翅膀活动时互不影响,使其可以突然停止或转向,在短时间内加速,甚至是向后飞行。

2013 年,我们的仿生团队根据这些高度复杂的性能开发出了一款超轻型飞行器,即 BionicOpter。首次将直升机、引擎飞机和滑翔机这三种飞机的飞行方式汇聚于一个机型 通过控制拍打频率和每个翅膀的旋转,我们可以根据方向和推力强度分别对四个翅膀进行调整。远程操控蜻蜓飞行器到达所在空间内的几乎各个角落。

集体飞行

2015 年,Festo 通过 eMotionButterflies 在轻型结构和微型化方面又迈近了一步,每只仿生蝴蝶的重量只有 32 克。为了尽可能地复制自然生物样板的飞行,eMotionButterflies 配备了高度集成的机载电子设备。它们可以精确且独立地控制各个机翼,实现快速移动。

安装在空间内的十台摄像机通过红外标记感测这些“蝴蝶”的位置, 然后将位置数据传输至中央控制主机,协调蝴蝶的运动。

在限定的空间内进行半自主地飞行

仿生工程师进一步开发了智能网络系统,并在 2018 年汉诺威工业博览会上展出了 BionicFlyingFox。通机载电子设备和外部摄像机系统的配合使用,FlyingFox 可进行半自主飞行。可使人工仿生蝙蝠以2.28米的翼展从空中飞过。

它拥有富有弹性的翼膜,从两翼一直延伸至后肢。该翼膜为专门研制,由一块氨纶织物和气密薄膜组成,通过选择性焊接紧密地焊接在一起。织物呈蜂窝结构,因此即便轻微受损,BionicFlyingFox 也能够继续飞行。

大自然中生物的飞行方式各有千秋——要将这些技术投入到科技研发中,需要面临轻量化与功能整合两大挑战。而BionicFlyingFox将所有高载荷运动学中的关节点置于同一平面内,以便整个机翼呈剪刀状折叠。至此,费斯托成功解密了动物世界中的已知的飞行方式。然而探索远没有结束。在大自然中,还有其他无与伦比的现象,启发着仿生研究团队发现新的科技方案。