## 2 Research Background and Related Work
### Related Work  
The rationale behind adopting agile (Scrum) practices to integrate the development of both hardware and software is provided by [PERSON] et al. who claim that \"the development of devices that combine hardware and software has created new challenges\", since \"the new built devices have a short life cycle and frequently require upgrading\" [49]. In this study, the authors introduced a development process so-called \"Agile and Co-Design\", which consists of seven phases and expected outcomes: Conception (product vision), Setting-up (specifications), Design (deliverables), Definition Of Done (checklist), Testability (integration tests), Implementation (hardware and software), Verification (evaluation). The findings show the application of their approach enabled deep interaction between teams representing different areas of knowledge, and fostered knowledge exchange and innovation creation.  
In a similar vein of cautionary optimism, [PERSON] stated that \"the benefits of incremental and iterative development of hardware may be as high as with software development\" [50]. However, afterward, the obstacles are articulated: \"the idea of incremental design was causing problems\", since \"people felt the hardware should have been created and tested as one entity\", and \"it is not flexible the same way software is\". On the other hand, the application of iterations \"can be used to mature the design\".  
The broad spectrum of issues and interests regarding the potential, transition and applicability of agile development in the hardware sector is given by [PERSON] and [PERSON] [51], and later by [PERSON] et al. [52]. The four categories of the findings concern:  
* constraints of physicality, the authors claim that \"the greatest hindrance is to realize potentially shippable increments in one iteration\", and as a consequence \"the technical feasibility to produce prototypes\" is hardly achievable in certain industrial branches, due to \"the inability to break down the product into modules\" [51];
* agile mindset, an individual attitude toward understanding, collaborating, learning, adapting and growing in the spirit of trust, responsibility and ownership, is pointed out as a major challenge for not only individuals, but also for the company;
* team distribution, the inability to work co-located resulted in a higher degree of communication needs between physically dispersed project participants (teams);
* scaling, the ability to apply the principles, practices and outcomes in other projects (horizontal scaling), or at other levels of the organization (vertical scaling), in order to change the way people approach their own work and working with others.  
Naturally, there are numerous other studies that have reported on the implementation of the agile approach, and its consequences on the project effectiveness and deliverables. Moreover, there are several well-known and admired industry corporations that are claimed to cultivate agile principles and practices, including Spacex [53], Tesla [54], General Motors [55], and Toyota [56], just to name a few. Nevertheless, agile is not a silver bullet that enables everyone to become adaptive, innovative, and resilient; neither is it an excuse to stop thinking, nor a panacea for solving all issues.