System map (MVP)

Horizon is an interactive system consisting of digital and physical controls for secondary infotainment system. The digital aspects contain the cluster display, the centre stack display and the HUD display. Whereas, the physical control is the slider knob.

System Map
Fig. 5.1: System map

The digital and physical controls of the systems are used for input and output in various contexts. Cluster and HUD are mainly for contextual output. Moreover, the touchscreen and slider knob are for more detailed feedbacks including selection descriptions, haptic and audio feedback.

Inputs and outputs
Fig. 5.2: Inputs and outputs

System Architecture (MVP)

To achieve the prototype, the team chose Protopie as a bridge to connect physical part (knob system) and digital part (screen system). For the screen system, three devices are prototyped as displays in car. For the knob system, different electronic components are programmed accordingly to the functions and interactions of the system.

System Architecture
Fig. 5.3: MVP System Architecture

Technical background processes

Fig. 5.4: Video showcasing the slider
Interaction: Grab
Fig. 5.5: Interaction: Grab
Interaction: Press
Fig. 5.6: Interaction: Press
Interaction: Slide
Fig. 5.7: Interaction: Slide
Interaction: Rotate
Fig. 5.8: Interaction: Rotate

System Architecture (Real Case)

The chart below represents the actual technologies representative of an implemented solution.

System Architecture
Fig. 5.9: Implemented System Architecture

Appearance model

Horizon team built basic interactions on a foam model using magnets and a rail to slide the knob on. Users are invited to interact with it to complete the given tasks like raising temperature.

Foam Knob
Fig. 5.10: Foam knob
Sliding the knob
Fig. 5.11: Sliding the knob

Technical Connections

Horizon team first starts from simple connections: slider & rotary button. The team sets the slider into 4 different zones which represent different setting — eg. temperature, music. Then the rotary button was used for both rotation and press interaction. The team also defines how each rotation and press means inside different slider zones.

For the detect and move function, the team attached a Sharp proximity sensor and a new motor to drive knob moving towards the user’s hand in close distance. The sharp sensor was used to detect where the user hand is and the result would be used to compare with where the knob position. The knob would be driven by a motor to move slightly to best fit into the user’s palm.

Linear potentiometer
Fig. 5.12: Linear potentiometer
Testing connections
Fig. 5.13: Testing connections
Linear potentiometer
Fig. 5.14: entire MVP system
Testing connections
Fig. 5.15: Circuit diagram
assembling the knob
Fig. 5.16: assembling the knob
box for components
Fig. 5.17: box for components

Interface development

Tools used: Protopie + Protopie Connect

UI of the navigation screen
Fig. 5.18: UI of the navigation screen
Cluster screen behind the steering wheel
Fig. 5.19: Cluster screen behind the steering wheel
Prototyping the HUD
Fig. 5.20: Prototyping the HUD

Whole system

The whole system is composed by 4 parts : console screen , cluster screen ,HUD & sliding knob. By Protopie, we have successfully controlled all three screens by sliding/rotating/pressing the knob. The team used different devices to prototype real car screens: Pad for console screen and cluster screen, iPhone & reflection film for HUD.

User testing the complete system demo
Fig. 5.21: User testing the complete system demo