Saturday, 18 September 2010

Heads Up Displays

Well, i was wondering what to write for my next post and i see this video of a BMW with a new kind of display implemented. That reminded me of the HUDs.

How about displaying all the information you need in front of your eyes rather than you seeing it on a display screen?? How about you get to use your mobile with just a pair of cool eye wear without touching or seeing your mobile phone often??

Well,that's how it feels to use a Heads Up Display(HUD).

HUD's came into first use in fighter planes,the idea of which was derived from the static gun sights used in WW2 Dog fighters. HUD's were seen in jets as early as 1958 in the Buccaneer strike aircraft. It was observed that the Buccaneer pilots had better piloting skills compared to other air crafts which had no HUD's. This led to the explosion of this technology in the coming days.

What if you get into a 8 lane straight road in your new car that can go really fast and u want to reach the maximum possible speed without violating any speed limits?? You'll have to constantly switch your vision between your speedometer and the road ahead. But what if your speed was displayed in your line of sight?? You never have to look at your instruments then :) This is the HUD technology being used in the auto industry today derived from the Jets.

So, basically a HUD is a transparent screen on which all the required critical information for the pilot is displayed so that he does not have to look at other dials very often.The origin of the name stems from the pilots being able to view information with heads "up" and looking forward, instead of angled down looking at lower instruments.

Shown below is a HUD from a Gulf stream Private Jet !!

Before reading what all the display mean, i should first tell about headings. Earth is considered as a circle. The North pole is true Zero,somewhere near Japan is your 90 degrees. This means that South pole is our 180 degrees and thus the whole of 360 degrees.

So, if i say that i'm heading 270, it means that from the point i have my plane,i'm heading west.

1.Actual Heading- Informs that the jet is cruising towards heading 244 degrees.
2.Set Heading- Informs that the jet is set to cruise for heading 245 degrees.
3.Pitch Ladder-Indicates the pitch at which the airframe is wrt level ground. You can see a 5 written at the other end of this line. This informs that the plane is at 5 degrees wrt horizontal level.
4.Flight Path Marker- Indicates the direction in which the nose of the plane is heading to.
5.Set Altitude Indicator- can read 24000. Means that the jet is set to fly at 24000 feet above the ground !
6.True Altitude Indicator- Its 23970- means that the plane is flying at 23970 feet.
7.Climb Rate- Reads 1013- means that the climb rate is 1013 feet/second.
8.Bank Angle Indicator- Currently reads 0 which means that the plane is not banked at any angle.
9.This must be some other general flight information about which i am not sure about :(
10.G-force Indicator- Reads 1 G-which implies that the people inside the jet feel the same gravitational force as they would feel on ground.
11.Set Heading- Reads 245 again. Dunno why this is made redundant in the display.

This is as far as i could understand from seeing the HUD. I so much tried to write with a fighter jet HUD,but could not get one with such high resolution as this.

However there is another version of the same heads up display technology- its the Helmet Mounted Display(HMD). Instead of using a transparent screen in the line of sight, its implemented on the helmet of the pilot.This is widely used in the Apache Attack Helicopter. Now, how about same technology on your bike?? The amount of information to be displayed may be far too less,but wont it be nice??

This technology is slowly coming into commercial jets and car industry too. Hope this post is easy to understand as the earlier ones:)


  1. Deepak about HUD's for our bike helmets ;) ?

  2. I second Nikhil :)That was a good insight about this awesome technhology

  3. @ Nikhil: Sure, the next time i come to mys,i'll fit one to ur helmet or on the visor :D Deal??

    @ Sindhu: We'll fix to ur vehicle also ;) Thanks :)