Aircraft interiors take years to develop, and big decisions need to be made early in this process. Mixed reality (MR) has the potential to help designers with this. However, current MR tools are technically complex and do not align with the speed and flexibility needed by designers. Happlo lets designers create MR prototypes in minutes so they can learn and iterate faster on their ideas.
Problem
Physical prototypes are too slow and expensive to test ideas early, when changes are still cheap. MR has potential to make prototyping faster and more flexible, but the current tools are too technically complex.
Approach
Challenges in the current design process of the team were mapped through interviews and project studies. Combined with a literature review and research on existing XR technologies, a problem was framed and a design goal was set.
Result
Happlo makes MR prototyping more accessible, faster and flexible, so designers can test more ideas earlier. This reduces prototyping costs, and reduces the risk of proceeding with the wrong thing.
The problem
Physical prototypes are too slow and lack context. 2D renders limit spatial judgement. Collins Aerospace’s design team shapes new seats, galleys and cabin layouts at the start of a process that can take seven years, and every mistake gets more expensive further into the project.
A rough foam mock-up already costs $1,000–5,000; the final version can cost up to $2 million. These physical prototypes can take months to build, and they often lack the context needed for UX evaluations. Many decisions are now made from just renders, which limit spatial judgement.
“Prototyping is one of the most important ways to help minimize the risk of proceeding with the wrong thing.”
Jeff McKee, Director Customer Experience & Design, Collins Aerospace Research and reframing
Interviews with designers, internal process documents, tests of existing XR tools and a literature review showed the potential of MR. Being able to touch what you see in a virtual scene makes people judge a design far more realistically. However, every existing setup needed a developer and careful technical calibration.
Designers require accessible, rapid, and flexible ways to experience, reflect on, and communicate their design ideas, using appropriate fidelity prototypes.
Mixed reality has the potential to help designers with this. While it is technically possible to create mixed reality experiences, current tools are development-intensive and are therefore poorly suited to the speed and flexibility required during an iterative design process. This defeats the potential of mixed reality to improve design workflows.
Research on perception showed that this precision isn’t needed. Vision dominates touch, so people barely notice when what they feel is slightly off from what they see. That insight influenced the design a lot.
Original question
Explore how immersive technologies can enhance the design process of Collins Aerospace’s Customer Experience and Design department.
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Design goal
Enable designers to create mixed reality prototypes by making the alignment of virtual and physical objects accessible, rapid, and flexible, allowing them to evaluate spatial design ideas at the appropriate fidelity without development-heavy preparation.
The approach
Happlo makes alignment of the physical and digital accessible, fast, and flexible with three design decisions
01 Align with your eyes In Alignment Mode, you select the virtual objects you want to feel, and they appear as holograms in your real room. You place the physical object on its hologram and switch back to the scene. No calibration, no developer.
02 Hands, not controllers Your hands need to be free to place and touch objects. The menu sits on your palm and only appears when you look at it.
03 Build only the touchpoints A seat, an armrest, a table edge: only what people touch is built physically, at whatever fidelity fits the moment. A scaffolding kit holds it in place and can be rebuilt in minutes.
Step 1 User enters the virtual scene The user enters the virtual scene with Alignment Mode turned off. If they want to create a mixed reality experience, they look at their left-hand menu and enable Alignment Mode. Step 2 Alignment Mode enabled When the user enables Alignment Mode, they are prompted to select the objects in the scene that they want to position physical touchpoints for. Step 3 Selecting objects In selecting mode, the user selects the virtual objects they want to align with physical ones, by pointing and pinching at them with their right hand. They can easily undo or reset as well. Step 4 Aligning objects The selected objects appear in the physical space of the user, at their location in the virtual world and with a reduced opacity. With these references, the user can now position the physical objects. Step 5 Back to the immersive scene After aligning the virtual and physical objects, the user turns off Alignment Mode. This brings them back into the immersive scene, where they can now interact with the objects they have just aligned.
Only the touchpoints are built physically at the appropriate fidelity; the rest around them is added virtually. This saves time and materials. Testing and iterating
The approach worked, and testing showed what to fix
Eight participants aligned objects in a room and then adjusted the armrest of a new business-class seat by sitting in it. Happlo scored 79 out of 100 on usability, and even when alignment was slightly off, touching the objects felt surprisingly real.
My first Alignment Mode made the whole scene semi-transparent, which overloaded people and made some dizzy. So I added a selection step: now only the objects you want to align appear as holograms.
Before: the whole scene semi-transparent. After: only the selected objects. The outcome
Happlo makes mixed reality prototyping more accessible, faster and flexible, so designers can test more ideas early
less time to build prototypes (estimate) 65%
lower prototyping costs (estimate) 70%
usability score (SUS) – before the last design iteration 79 The real saving is in what that enables: being able to reduce the risk of proceeding with the wrong thing before it gets expensive.
Reflection and next steps
Next: from a rough sketch to a scene you can touch
What started as an XR space for Collins became Happlo: a technique any industry can use. Designers wanted to start using it, so I proposed an implementation strategy with a business case. Collins is now discussing next steps.
Testing also showed the next bottleneck: preparing the virtual scene in Unreal Engine still asks too much of designers. That makes the timing of this project good. AI asset generation is making that step much easier, so a designer can go from a rough sketch to a 3D model in a virtual scene that they can actually touch. The next step is an app of its own, where that whole flow comes together without Unreal Engine.
What I took with me: an idea gets built when you show what it saves in time, money or risk, not only how much nicer it is to work with. Meanwhile, I’m bringing Happlo to Apple Vision Pro in a hobby project .
Master thesis · TU Delft
Happlo: A Lean Approach to Mixed Reality Prototyping
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