Elaborate cutaway model provides insight: Electric mobility becomes transparent
Stuttgart. With a transparent EQC 400 4MATIC (combined power consumption: 21.3-20.2 kWh/100 km; combined CO2 emissions: 0 g/km), trainees of Mercedes-Benz render the innovative technology of the electric car visible. The left half of the vehicle was left in the original condition and the right half was fitted with cuts in the vehicle body and in the floor. This offers a view of otherwise concealed components such as the battery, for example. Cutaway models of individual components, a simulation of the charging process by means of LED chase lights and a virtual overlay of the high-voltage battery on a tablet PC complete the elaborate exhibit.
Some 40 trainees from the occupational groups vehicle mechatronics specialist, interior fitting specialist, construction mechanic and tool mechanic were involved in the project. The employees come from the Sindelfingen, Bremen and Rastatt locations. Including the interruption due to COVID-19, this team worked for about a year on building a transparent EQC from a donor vehicle and a body shell. At the same time, they created a host of cutaway models of individual components such as on-board charger, cockpit, bumpers or headlamps. They were integrated into the large showpiece. This practical work on an electric vehicle allowed important learning content to be imparted to this year's trainees.
Charging and discharging of the battery is simulated by means of LED chase lights along the charging peripherals of the vehicle. The original screens of the EQC were reprogrammed to allow displaying and playing of explanatory images and videos. In addition, an augmented reality (AR) application on a tablet PC allows virtual overlaying of the high-voltage on photos of the EQC.
Here are some facts and figures:
- Approx. 15 metres of LED fibre optics are installed
- Around 50 metres of wiring are installed to power the LEDs.
- Over a 36-hour period, 3 trainees used up 8 grinding discs to cut 5 apertures in the bodywork. In addition, 23 woven abrasive belts were used up to deburr the cut edges.
- The painting and polishing work took a total of around 50 hours.
- Two Arduino microcontroller boards with 3 relay shields for control of the LED strips and locking, and the LED display on the charging socket. The programming code has a total of around 500 lines.
- The trainees took 21 hours to turn the three light bands at the rear into one; a further 18 hours was needed to turn two tail lights into one using a Dremel and jigsaw.
- Preparing the reversing camera took 10 hours.
- All in all, the team came together in around 650 minutes of online conferences. Each morning another 20 minutes were spent on digital shopfloor management (working organisation)
- Two "Next Unit of Computing" (NUC) mini-PCs by Intel with 2 video converters were used to reprogramme the monitors - the programme code has around 1500 lines.
 The power consumption was determined on the basis of Directive 692/2008/EC. The power consumption is dependent upon the vehicle configuration. Further information on the official fuel consumption and the official specific CO2 emissions of new passenger cars can be found in the "Leitfaden über den Kraftstoffverbrauch, die CO2-Emissionen und den Stromverbrauch neuer Personenkraftwagen" [Guide to fuel consumption, CO₂ emissions and power consumption of new passenger cars], which is available free of charge at all sales outlets and from Deutsche Automobil Treuhand GmbH at www.dat.de.