Experimental/Hobby Market Entered With Low Cost Unit.
By ANN Correspondent Christopher Armstrong
Crossbow Technology is
working on several AHRS systems for certified aircraft as well as
for experimentals and even UAVs. While walking through the main
display hangers at AirVenture 2005 last week, I came across the
Crossbow Technology booth.
Mike Horton, President and CEO of Crossbow Technology, happened
to be in the booth and he began to describe the biggest of the
shiny gold anodized aluminum boxes in the display. It was a
certified AHRS being used in the Eclipse 500 very light jet, and
other certified aircraft. It provides pitch attitude, yaw attitude
and magnetic heading to very high accuracy over a very wide range
of temperatures, aircraft vibration characteristics and electronic
noise. I didn't ask how much it cost.
Next he showed me a very similar, but non-certified AHRS for
experimental aircraft. This unit had most of the same features, is
nearly as accurate and adds GPS navigation capability, and it
probably costs a lot less, but I didn't ask. Horton told me about
the next product that Crossbow was bringing out would be a
certified AHRS with ARINC429 that they plan to have certified by
the end of 2005. Who knows what that will cost?
I figure the shiny gold things are gold for a reason, they are
super accurate and that means expensive. I noticed a little (2.25"l
x 1.8"w x .44"h) block of circuit boards sitting on a table. It was
made up of three separate boards at 90 degrees to each other and
had a large set of pins for a plug on one side. This uncased little
unit looked like it might be more affordable.
I pointed past Horton and asked him to tell me about the chip
cube. He said it is the MNAV100CA. It is intended for the hobbyist
and experimental market. It includes 3 rate gyros, three
accelerometers, three flux gate compasses, a gps receiver, 8
channels of radio control reception and open software called
MICRO-VIEW that will allow customization for individual use. It
will cost around $1500.00. Now I got really interested.
I asked about the accuracy and he told me that it wasn't going
to be nearly as good as any of the other units but their
specifications, listed below, don't look too bad for the intended
market. I don't think anyone would want to go scud running using
this data, but it would drive an autopilot, and a moving map
display fairly well. With the 8 channels of remote control and open
architecture software, Hobbyists will be able to make ready to fly
UAVs out of the box.
An additional board called the Stargate Processor Board (SPB400)
is a complete Low-Power, Small-Size, 400MHz, Linux Single Board
Computer that connects to the Micro--NAV via a standard 51-pin
connector to form a complete robotic development platform. It
includes telemetry via WiFi for commands and data, and closed loop
navigation control. Any onboard sensor, like a USB video cameras,
can be connected to and processed by the Stargate board with data
downloaded real time via the WiFi. The bare Stargate Board is an
additional $489, but the more complete Advanced Stargate Kit is
$1000.
Anyone looking to build their own UAV Robot, or to add some
really cool data and autopilot functions to an experimental VFR
aircraft should look into this affordable little bundle of sensors.
For around $2500, you could fly your ultralight by remote control
while collecting as much data as a military reconnaissance
drone.
Specifications:
Update Rate 1-100 Hz
Angular rate range +- 150 degrees/sec
Acceleration range +- 2 g
Inertial sensor bandwith >25 Hz
Magnetometer range +-0.75 g
Altitude range 0-16404 feet
Airspeed range 0-179 mph
GPS accuracy 9.8 feet
Temperature range 23-113 degrees Fahrenheit
Input voltage 3.7-16 VDC
Power consumption <0.8 Watts
Digital output format RS-232