Jemba Inertia Notes System
Encyclopedia
The Jemba Inertia Notes System is a computer software program used in rallying
that automatically prints out stage notes
for competitors to use. The purpose of the system is to allow organizers to create a consistent set of pace notes
for all the competitors without having them take to additional time and resources to do the reconnaissance themselves. Currently, the system is used most heavily in the Rally America National Championship
but is also used greatly for national championships in Canada, Sweden, Norway, New Zealand, and Great Britain.http://www.jemba.se/notes.htm
The system was developed by Jemba, a Swedish-based company that specializes in making and selling of a limited scope of rally-specific products. In addition to their inertia notes system, they are a distributor for Peltor helmets, and Coralbra rally computers (odometer
) on which the notes system runs.http://www.jemba.se
Various instruments are used to collect information on the track:
Co-driver, or Navigator - During a rally, the car driver is accompanied by a co-driver or navigator, who, through the use of stage notes or pace notes, is responsible for keeping the driver on course and on time.
Stage Notes/Pace Notes - Read by the navigator, a set of detailed instructions describing every turn, hill, jump, obstacle, and distance between instructions in precise, detailed code language.
Reconnaissance - A pre-running of competitive sections of the course to create the pace notes or stage notes.
and a series of accelerometer
s (hence “inertia”) inside a car. The odometer is used to calculate precise distances between instructions and to give the location of the instructions. The accelerometers sense turns, bumps, and hills in order to give consistent grading of corners and crests in the printout. The terminology used in the printout is then defined by the user of the system.
To use the system, the user connects the laptop to the odometer and accelerometers inside the car. The user then drives the stage, a competitive section in rallying, at normal speed in the middle of the road. By going much slower than competition speeds, the accelerometers are less prone to inaccuracies, and by driving in the middle of the road, a more accurate description of the road is given (that isn’t biased to one side or the other). Then, the system prints out a description of the road based on the user's pre-defined preferences and allows the user to then make any manual changes he/she feels are necessary
American System
http://www.jemba.se/notesUSA.htm
New Zealand System
http://www.jemba.se/notesnz.htm
While the US system goes from one to six, one being the slowest, six being the fastest, the New Zealand System goes from one to eight (eight being the fastest, one being the slowest). Also, the directional term (L for Left, R for Right) is shown in front of the numeric term in the American system and following the numeric term in the New Zealand system.
Margin for critical braking distance before stop.
This is how far you may carry on at competitive speed until you have to start braking to be able to stop at the stop control.
Used of available braking dist before stop (%)
This tells how many percent of the available braking you will have to use if you brake to the maximum.
Jemba Safety Index (J/kg)
Jemba Safety Index gives average kinetic energy in the car through corners, that is the average energy available to cause damage on places where the car slides.http://www.jemba.se/inertia.htm
Rallying
Rallying, also known as rally racing, is a form of auto racing that takes place on public or private roads with modified production or specially built road-legal cars...
that automatically prints out stage notes
Pacenotes
In rallying, pacenotes are a commonly used method of accurately describing the route to be driven in extreme detail. As well as dictating the general route to be taken, in terms of turnings, junctions, etc, all notable features of the route which might affect the way it is driven at speed are...
for competitors to use. The purpose of the system is to allow organizers to create a consistent set of pace notes
Pacenotes
In rallying, pacenotes are a commonly used method of accurately describing the route to be driven in extreme detail. As well as dictating the general route to be taken, in terms of turnings, junctions, etc, all notable features of the route which might affect the way it is driven at speed are...
for all the competitors without having them take to additional time and resources to do the reconnaissance themselves. Currently, the system is used most heavily in the Rally America National Championship
Rally America
The Rally America National Championship is the national championship of rallying events in the United States. The inaugural season was in 2005. Rally America was also the name given to the organization that sanctioned the championship, was briefly rebranded to RallyCar in July 2010, then reverted...
but is also used greatly for national championships in Canada, Sweden, Norway, New Zealand, and Great Britain.http://www.jemba.se/notes.htm
The system was developed by Jemba, a Swedish-based company that specializes in making and selling of a limited scope of rally-specific products. In addition to their inertia notes system, they are a distributor for Peltor helmets, and Coralbra rally computers (odometer
Odometer
An odometer or odograph is an instrument that indicates distance traveled by a vehicle, such as a bicycle or automobile. The device may be electronic, mechanical, or a combination of the two. The word derives from the Greek words hodós and métron...
) on which the notes system runs.http://www.jemba.se
Definition list
Rallying – A motorsport which involves both a driver and a co-driver/navigator. The sport uses street cars first retro-fitted with improved equipment and safety systems, and then driven competitively around closed roads in the wilderness.Various instruments are used to collect information on the track:
- Speedometer – An instrument common to almost all motor vehicles, the speedometer determines the instantaneous travel speed of the car, based on an intricate system of magnets and gears.
- Odometer – Also common to all vehicles, the odometerOdometerAn odometer or odograph is an instrument that indicates distance traveled by a vehicle, such as a bicycle or automobile. The device may be electronic, mechanical, or a combination of the two. The word derives from the Greek words hodós and métron...
tracks the rotation of the car’s wheels to determine and display the distance traveled by the vehicle.
Co-driver, or Navigator - During a rally, the car driver is accompanied by a co-driver or navigator, who, through the use of stage notes or pace notes, is responsible for keeping the driver on course and on time.
Stage Notes/Pace Notes - Read by the navigator, a set of detailed instructions describing every turn, hill, jump, obstacle, and distance between instructions in precise, detailed code language.
Reconnaissance - A pre-running of competitive sections of the course to create the pace notes or stage notes.
Technical
The Jemba Inertia Notes System comes in the form of software loaded onto a laptop. The laptop is connected to an odometerOdometer
An odometer or odograph is an instrument that indicates distance traveled by a vehicle, such as a bicycle or automobile. The device may be electronic, mechanical, or a combination of the two. The word derives from the Greek words hodós and métron...
and a series of accelerometer
Accelerometer
An accelerometer is a device that measures proper acceleration, also called the four-acceleration. This is not necessarily the same as the coordinate acceleration , but is rather the type of acceleration associated with the phenomenon of weight experienced by a test mass that resides in the frame...
s (hence “inertia”) inside a car. The odometer is used to calculate precise distances between instructions and to give the location of the instructions. The accelerometers sense turns, bumps, and hills in order to give consistent grading of corners and crests in the printout. The terminology used in the printout is then defined by the user of the system.
To use the system, the user connects the laptop to the odometer and accelerometers inside the car. The user then drives the stage, a competitive section in rallying, at normal speed in the middle of the road. By going much slower than competition speeds, the accelerometers are less prone to inaccuracies, and by driving in the middle of the road, a more accurate description of the road is given (that isn’t biased to one side or the other). Then, the system prints out a description of the road based on the user's pre-defined preferences and allows the user to then make any manual changes he/she feels are necessary
Regional variation
In order to be usable across the world, the system takes into account regional variation. The printout can be changed to adapt to different languages, terminology, or preferences. On the company’s website, a comparison of the system used in New Zealand is shown to be much different than that of the United States by using a different scale and terminology.American System
| Descriptive Term | Flat or fast plus (Fastest corner) | Flat or fast | Easy plus | Easy | Easy minus | Medium plus | Medium | Medium minus | Kay plus | Kay | Kay minus | Bad plus | Bad | Bad minus | Hairpin plus | Hairpin, (Slowest corner) |
| Numeric Representation | L/R6+ | L/R6 | L/R5+ | L/R5 | L/R5- | L/R4+ | L/R4 | L/R4- | L/R3+ | L/R3 | L/R3- | L/R2+ | L/R2 | L/R2- | L/R1+ | L/R1 |
New Zealand System
| Descriptive Term | Absolute (fastest corner) | Easy + | Easy | Easy - | Flat + | Flat | Flat - | Medium + | Medium | Medium - | Kay + | Kay | Kay - | Square | Hairpin | Tight hairpin (slowest corner) |
| Numeric Representation | 8L/R | 7L/R+ | 7L/R | 7L/R- | 6L/R+ | 6L/R | 6L/R- | 5L/R+ | 5L/R | 5L/R- | 4L/R+ | 4L/R | 4L/R- | 3L/R | 2L/R | 1L/R |
While the US system goes from one to six, one being the slowest, six being the fastest, the New Zealand System goes from one to eight (eight being the fastest, one being the slowest). Also, the directional term (L for Left, R for Right) is shown in front of the numeric term in the American system and following the numeric term in the New Zealand system.
Extra features
In addition to a printout of the notes, one can also get a graphical plot of the stage, numeric information about the stage, and a graph showing the speed profile over the complete stage for a simulated run with a user-defined specification of a rally car that might be competing.Margin for critical braking distance before stop.
This is how far you may carry on at competitive speed until you have to start braking to be able to stop at the stop control.
Used of available braking dist before stop (%)
This tells how many percent of the available braking you will have to use if you brake to the maximum.
Jemba Safety Index (J/kg)
Jemba Safety Index gives average kinetic energy in the car through corners, that is the average energy available to cause damage on places where the car slides.http://www.jemba.se/inertia.htm
