Telemetry systems are used to send data from Logging Systems or Data Acquisition
Systems using various sensors - strain gauge, rotational torque etc - and send
this data to a remote station for monitoring and analysis. Most telemetry
systems utilise radio signals to send the data. The transmitter can be
configured to send the data anywhere from a few millimetres to several miles
depending on the application. For some applications, the telemetry is required
because the sensor is mounted on a rotary shaft making physical connection all
but impossible. In others the telemetry is required as the sensors are mounted
on a moving object like an automobile or aircraft.
Data logging and Recording systems
Data logging and Recording systems consist of four elements:
1. Measuring output (sensors around the vehicle)
2. Recording output signals (logger unit or
Data Recorder)
3. Uploading/accessing recorded data (Telemetry
Systems)
4. Analysis of recorded data. (DAS software)
The 4 elements above have specific requirements which need to physically
present and included in the design process. Sensors to measure selected
parameters must meet certain specifications, and the routing of the sensor
cables ensures they will not suffer from electromagnetic interference from other
electronic systems. The DAS unit (including memory) and the link from the DAS
unit to the operating platform to upload the acquired data via a hardwire cable
or telemetry also must conform to requirements.
Most race cars use two types of telemetry.
The first is sent to the engineers in the pits every time the vehicle acquires
more than 50Mb of data, containing an insight into the state of the vehicle. The
second is transferred each time the vehicle is in the pit lane, providing
information on every part of the vehicle. With the most advanced telemetry, the
data is sent constantly for analysis through a transmitter as long as a good
connection is present usually thru a hovering helicopter (not always possible in
parts of certain raceways due to an overpass obstruction).
The operating platform is required to include specialist analysis software to
view the data, usually in the form of various graphs to improve and develop the
performance of the key areas and operation parameters of the vehicles running
conditions. The most advanced software in Formula 1 has been developed by
McLaren Electronics known as Advanced Telemetry Linked Acquisition System, which
displays graphs of each of the vehicle's systems on the exact section of track,
in a real time format. The benefits of using such a system include the fact that
the parameters which can be recorded for analysis cover the whole set-up of the
race vehicle (up to 127 channels).
The parameters which are measured and recorded by a data acquisition system
are broken into three generic categories, which are also interlinked due to
system requirements and the complexity of major components (for example, a wheel
speed sensor not only monitors the wheel speed but also the speed of the
vehicle, location on the track and an input to traction and launch control
systems):
Engine: Revs per minute, fuel and oil pressure, water and oil temperature,
turbo charger boost pressure, exhaust gas temperature, battery voltage, inlet
air temperature and throttle position sensor.
Chassis: Wheel speed, steering angle, lateral and longitudinal G-force
(applied from braking and cornering), Brake line pressure, damper movement and
gear position. * Advanced Chassis DAS: Ride height, drive shaft or prop shaft torque,
suspension loads, tyre pressure and compound temperature, and brake disk
temperature. Optional: aerodynamic parameters, including air speed and local air
pressures.
Driver: Both engine and chassis-related factors which are controlled by the
driver, such as throttle position, gear position, steering angle and brake line
pressure or directly controlled parameters such as engine revs per minute, speed
and G-force.
The accurate information provided by telemetry sent by DAS in a practice run
takes significant fine tuning, such as ensuring the correct gear ratios are
present according to track layout, or that the engine acceleration speed
according to throttle position and sensitivity is set to the required conditions
of a race. The engine control system will be programmed with suitable engine
maps giving the driver more control of the throttle input. On a track with a
large number of corners, the first part of pedal movement would be made very
sensitive in order to effectively negotiate the course. On other courses,
however, the vehicle might be required to come out of the chicanes and directly
to peak power levels, thus less sensitivity required on the pedal.
The DAS during race time is monitored by engineers in the pit and garage
area, who diagnose any faults which may occur. In this case, the DAS is used as
an early warning system of potential mechanical failure, allowing the designers
and material analysis team to easily distinguish the cause of the fault. This
can result in a significant decrease of the danger to a driver.
Race strategists and engineers can use DAS with telemetry in real time for
making more informed decisions pertaining to vehicle performance and driver
technique. Information about other vehicles on the track can also be captured
and added to the data analysis process. Total data from a motor sport event may
exceed 80 gigs of storage space. A new technology born from Associate Systems
research or artificial intelligence (AI) has increased the safety factor for
spectators, drivers, and officials.
A good example for critical data acquisition systems in motor sports can be
taken from the 2003 British Grand Prix, when engineers in the pits observed the
loss of pressure from one of Coulthards tyres. The DAS allowed the team to
recall him from his practice, resolving the fault before a dangerous situation
occurred, likely saving property and life.
“Formula 1 telemetry is the technological lifeblood of the sport, helping the
drivers and engineers to better understand how a car functions and how they can
optimise its set-up
