Mid Gauge Panel
The mid gauge panel includes the following elements:
- Two fuel level indicators
- Left and right alternator load indicators (Amps)
- Bus voltage indicator (Volt)
- Ambient temperature indicator (Celsius)
- Ambient pressure indicator (hPa)
- Three air vent outlet nozzles
Upper four Gauges
Instead of my implemented ambient temperature and pressure indicators, the virtual Beech Baron cockpit holds a Propeller Amps and an De-icing Pressure gauge. However I thought that my implemented indicators will give me as pilot more useful information.
The four round upper indicators are designed in CAD and the individual parts were then 3D printed. The needles are driven by micro-servos, because the required turn angle is smaller than 180 degrees. The scale layout was designed in Power Point and has been printed on glossy photo paper by an inkjet printer. To protect the scale and the needle from dust, all indicators have a Plexiglas cover. Because the indicators are relatively small, I did not plan to include LEDs to illuminate them.
For the fuel level indicators I had to apply some software tricks, because the scale is not a linear one to highlight the information of the first half of the fuel level. I therefore had to implement two different conversion functions to drive the servo. In contrary to this, the temperature and pressure gauges have an exact linear scale.
Alternator Load and Bus Voltage Indicators
The intension for the alternator load and bus voltage indicators was, to use these type of commercial indicators, which are commonly used in audio equipment's to show for instance the audio signal strength. However, these are by far too large and do not fit into this panel. It was therefore decided to build them from scratch, which however is not an easy undertaking.
The result was, that my 3D printer had to start the next jobs. Without going into the details, this device consists of three micro-servos, the associated gear trains and long lever arms for the needles, as shown in the right picture. These long lever arms were necessary to keep the scales as flat as possible. The last job was to design and print some kind of bezels, including Plexiglas covers, which are inserted into the panel.
Designing and printing the individual pieces is one part of the story, but assembling and aligning them is another business. It took a while until I also managed this job, including the design of the driving software and their adjusting parameters to ensure, that the needles are always standing at the correct position. It shall be highlighted, that all seven micro-servos are driven by dedicated Servo Slave Controllers, which are located within the Engine Gauge unit.
Air Vent Nozzles
Because the intention is to close the cockpit by a cabin, there is also a need for fresh air, when two persons are flying, because in some flight situations it can become really hot and musty. Therefore three dedicated air vent outlet nozzles are implemented in the lower part of the panel.
Each air vent nozzle consists of a ring, having a negative sphere segment, a cover and a backside fixation ring. The cover is mounted into the ring, so that it can be tilted. In addition, the complete ring can be turned in any direction to ensure, that the air vent can go in any direction. All parts are 3D printed, painted black and mounted into the mid lower panel.
Behind the air vents there is a fan, typically the ones used for PCs, generating the air vent. This fan can be adjusted to low or high speed, while the associated switch is located in the left lower panel.