Zero Off · increase your pull or load on the rope, reducing the boat’s speed. And the same is...

Zero Off VERSION R

International Waterski and Wakeboard Federation

USA Water Ski

American Water Ski Association

Will Bush

willbush@att.net

+1 (916) 837-7464

Rev Date 04 / 01/ 2013

Zero Off GPS Speed Control System

New Displays beginning 2013

Expect to see other boat manufacturers to do the same

What else is NEW for 2013?

– Version R Approved for use – USAWS / AWSA Towboat Tests

– Slalom – NEW “+“ PLUS features

– Jump – RTB modified so that speed returns to the set speed in 41m

segment

– Jump - Change times displayed to 3 --52m, 82 m, and 41 m segments.

– User selectable TORM (Throttle Over Ride Mode)

– River Mode option added for use to compensate for any water currents.

– New option that changes system settings with different propellers – 3

blade or 4 blade (MasterCraft, Malibu, Centurion)

– Provides set up option with initial installation to choose different engine

options.

– Discourages a driver from limiting or blocking the throttle in slalom.

When the system detects an insufficient throttle handle position, it will

gradually slow the boat by 2 kph

• Zero Off uses data from GPS satellites to determine speed and

location; and uses its internal accelerometer (your smart phone

also has one of these) to instantaneously determine if the boat is

decelerating or accelerating; and communicates with the

ECM/ECU (engine control management system) to control speed

control and provide you course timing data.

• The GPS antenna(s) can receive signals thru glass or plastic, but

not solid objects. The antenna(s) should have a clear view of the

sky and ideally not be blocked by trees, nearby structures or

mountains.

• Zero Off can map slalom and jump courses, utilizing the GPS

location data, and store them in memory. However, care should

be take to confirm course precision before an event. As times,

there can be a significant difference between the timing “beep”

and the location of the start to entrance to the course. If this is the

case, the system should be re-mapped.

BASICS - How does ZO get its Information?

Zero Off uses signals from the worldwide US - GPS satellite system

GPS Minimum - 24 satellites orbit the earth at any given time.

Satellites in 6 planes, each with at least 4 satellites equidistant.

Orbits range from 55° north to 55° degrees south.

At least four satellites can be received at any time at any place

in world.

Closer to the poles, the lower over the horizon the satellites are

located.

Can still be received, but they are not directly above. This could

result in a – “typically” insignificant - loss of the precision of

position

ACCURACY ??? - WAAS (United States) / EGNOS (Europe)

Errors are created when GPS signals pass through the earth’s atmosphere (reflected &

slowed). Result – less than ideal location information (accuracy within 10 meters or better)

WAAS (covering USA), and EGNOS (covering Europe) are similar systems/satellites

which provide correction information and more precise location for Zero Off. These

satellites are stationary over the equator and broadcast on the same frequency as GPS

satellites.

The WASS/EGNOS use readings from ground stations that are in a known fixed

positions. The fixed ground stations compute the exact distance to each satellite,

measure ionospheric lag and tell any nearby GPS how much to correct -- "Differential

GPS" (DGPS). (accuracy within 1 – 2 meters or better).

Zero Off with use error differential data automatically - whenever it can see the satellites

above the equator.

Number of Satellites and DGPS Correction

Each .001” latitude

equals approx 6 feet

Obviously GPS is NOT

Working – check GPS

pucks – use Diagnostics

screen to troubleshoot

8 Satellites with

DGPS

8 Satellites N0 -

DGPS

SLALOM

New “+” Setting.

Separate variable from

“LETTER/NUMBER”

Don’t forget to change

for next skier!!!

Slalom General Information

Zero Off is a speed based control system. It constantly strives to

maintain the Set or Target Speed and will do so through the

entire course. Before the entrance gate, the speed is elevated to

compensate for the load you will apply going thru the entrance

gate. In the course, Zero Off does not gas you – it only responds

to what you do!

Zero Off Does NOT gas you!

As a general rule, in slalom, Zero Off ONLY responds when you

increase your pull or load on the rope, reducing the boat’s speed.

And the same is true when you let up on your pull or load on the

rope, increasing the boat’s speed. In other words, Zero Off

ONLY reacts to changes in boat speed and does NOT “gas” you

on its own.

Slalom Points For Discussion

• Letters/Numbers/”+” settings -- What they do?

• Can a skier change the letter/numbers during their ski ride?

• Shortcut – How do I to recall times from earlier passes

• Slalom Wait Timer – How to set the WAIT time

• JUDGE - WHY do I hear ZERO OFF constantly “BEEPING” (more that

just at the timing points) as the boat and skier go down the slalom

course?

• JUDGE - Why don’t I hear the beeper? Why is the volume off?

• JUDGE – Am I checking to ensure that the “beep” /timing process is

occurring when the GPS puck is precisely at the slalom entrance gate?

(Does the system need to be re-mapped?)

Letters / Numbers SLALOM

• Version Q – Previously 9 Letter / Number combinations

• Version R Slalom Changes – “+”

– Retains the original 9 settings from Version Q. Adds 9 additional

settings with “+”

– Now 18 Letter / Number combinations

– The “+” setting does things: 1) increases the speed outside the

entrance gates and; 2) makes the engine response faster for

each letter setting

“+” Setting

– Generally, heavier / stronger skiers may prefer the plus “+”

setting, looking for a faster start and quicker throttle response.

– The faster speed outside the entrance gates and quicker engine

response ensures that for the stronger skiers, the boat /engine

does not fall behind; eliminating any “catch up” and the feel of

“gassing” the skier into the next buoy.

– The “+” setting is a SEPARATE variable from the LETTER

setting. When the “+” is active (visible), the speed before the

entrance gate will be FASTER and the boat WILL respond

QUICKER for each letter setting. Be certain you RETURN to

the “Normal” setting for the next skier!!!!

Version R - Letters / Numbers / “+” We will discuss …

A1

A2

A3

B1

B3

B3

C1

C2

C3

A1+

A2+

A3+

B1+

B3+

B3+

C1+

C2+

C3+

“NORMAL” PLUS “+”

Faster entrance gate

Quicker engine response

Letters • The LETTERS dictate how quickly the engine will respond. In other words,

WHEN Zero Off begins to apply throttle.

• You have the option to select a letter that responds differently to your PULL

and your RELEASE from that pull.

• PULL -- As you begin your pull the boat speed begins to drop below the

SET/target speed. The letter tells the engine how QUICKLY to begin to

apply power to get back to the SET speed.

• RELEASE -- As you let up on your pull the boat speed begins to rise higher

than the SET/target speed. The letter tells the engine how QUICKLY to

reduce power to get back to the SET speed

• Each letter gives you different options depending on your style and

preference. Remember that NO two skiers are alike. You will need to find

what works best for you!

Letters - PULL

PULL – with a skier’s pull, boat speed will FALL and the engine will

respond to maintain the set speed

• The LOWER the letter, the LONGER it will take for the engine to

respond to speed drop.

• Conversely, the HIGHER the letter, the FASTER the engine will

respond to speed drop.

• NOTE: “A” is the “lowest” letter.

• For each letter setting, the “+” provides faster engine response.

This will benefit skiers looking for immediate reaction from the

engine / throttle. (NOTE: The engine will respond quicker on

“A+” than on “C”.

• LOWER LETTER = SLOWER ENGINE RESPONSE (to your pull)

A B C A+ B+ C+ SLOWEST

RESPONSE

FASTEST

RESPONSE

Letters - RELEASE

RELEASE –as the skier releases his pull, boat speed will RISE.

• The HIGHER the letter , the LONGER it will take for the engine to

reduce throttle.

• Conversely, the LOWER the letter, the FASTER the engine will

reduce throttle.

• For each letter setting, the “+” provides faster engine response.

• HIGHER LETTER = SLOWER ENGINE RESPONSE (to your release)

(in this case - the fastest release is A+ / slowest release is C)

Letters IT’S WHEN YOU PULL (AND HOW HARD YOU PULL)

- NOT WHERE YOU PULL!!!

• Remember, that Zero Off responds to your pull and release;

and not to “WHERE” you are in the course. SO, regardless

of the letter, it is “WHEN” you pull not “WHERE” you pull.

In selecting a letter, know that the faster the boat recovers

speed, the sooner it can release the skier.

• IN THE END, each skier needs to find what works best for his

or her personal style. Since no two skiers are alike – some

pull or load the boat out wide, some at the buoy and others

closer to the wake, each setting will produce a different feel

within the rules. In other words, your friend’s setting may not

be best for you!!!

Numbers Dictate the INTENSITY of throttle Response

• The numbers dictate the INTENSITY of throttle / engine

response to your pull. In other words, HOW MUCH throttle to

apply

• With a lower number, the feel of INTENSITY of the throttle will

be less, with a longer duration to get back to the set speed.

• With a higher number, the feel of INTENSITY of the throttle will

be more, but with a shorter duration to get back to the set speed.

• With “+” , throttle intensity will INCREASE. Typically ONLY

heavier / stronger skiers will benefit from use of the “+” settings

LESS

INTENSITY

MORE

INTENSITY 1 2 3 1+ 2+ 3+

The Letters Skier’s view …..

A. Letter A favors a smoother, longer turn and provides more time for proper

body position before the pull from the boat increases. The A setting results

in a slower engine response to the skiers load on the boat, meaning the

skier will move closer to the wake before the pull from the boat increases.

Letter A provides the fastest release as the skier lets up on the load;

however, the entire process happens later than Letters B &C.

B. Letter B favors a skier looking for a balanced pull and release from the

boat. Setting B2 is the “default” setting and should be used when the skier

does not choose another setting. The B setting is best described as a

moderate engine response. The boat’s rpm will increase earlier than with

setting A. The release is symmetrical with the load.

C. Letter C works particularly well for a skier whose style includes a faster

turn. The C setting gives the fastest engine response to the skiers load on

the boat, meaning the pull from the boat will come on very close to the

finish of the turn. The release is a bit slower that the other letters.

The Letters MORE than you wanted to know!

A. With Letter A, the PULL value is slower and the RELEASE value quicker. For both

letters A & C, the PULL & RELEASE values are different (Asymmetric Load &

Release)

B. For letter B, the PULL and RELEASE values are the same. (Symmetric Load &

Release)

C. With Letter C, the PULL value is quicker and the RELEASE value slower. For both

letters A & C, the PULL & RELEASE values are different (Asymmetric Load &

Release)

Numbers How does this happen?

• When throttle is applied, the amount or INTENSITY is dictated by the

number selected.

• HOW does change in INTENSITY happen? Initially, throttle is applied to

counteract the skier’s slowing of the boat. Zero Off can measure the skiers

load (g-force*). When the skier’s load reaches a predetermined load point,

Zero Off begins to reduce the rate of adding throttle. This reduction in

throttle rate is felt by the skier. The lower the number the sooner the skier

will feel a reduction in the INTENSITY of the pull from the boat.

*g-force (with g from gravitational) is a term for acceleration felt as weight and measurable by an accelerometer.

Numbers MORE than you wanted to know (Engineer’s perspective)

• An accelerometer measures the skier’s force or load on the boat.

• When the skier’s measured force (g-force) is reached, any rate of

additional throttle is reduced as boat attempts to get back to the

set/target speed.

• The lower the number the sooner the skier will feel a reduction in

the INTENSITY. In other words, it requires less force for a change

in throttle rate to occur.

Entrance Gate Speed

• The elevated or “target speed”, outside course (entrance

gate) is a percentage of the “set speed”

• Using the “normal” setting, Gate Speed is +.75 % above the

set speed

• Using the plus “+” setting, Gate Speed is +1.6 % above the

set speed

1: The “1” setting requires the least amount of skier pull or force to initiate a change in

throttle rate. The “feel” will be an overall softer pull behind the boat. If your goal is to

minimize line tension, taking a more conservative cut into the wakes, you will benefit

from this setting’s response.

2: The “2” setting is the midpoint setting. It requires a comparatively moderate amount

of pull to initiate a change in the rate throttle is applied. The “feel” will be slightly

stronger behind the boat than with setting 1. Like setting B, this is a good starting

point for most skiers looking to familiarize themselves with the system.

3: The “3” setting requires the greatest amount of pull to initiate a change in the rate

throttle is applied. The “feel” will be a stronger pull. If you are a big cutter, taking a

good amount of load into the wakes, you will appreciate the stiffer pull.

“+” The “+” setting requires even more skier load than the “normal” setting 1 / 2 / 3, to

initiate any change in the rate throttle is applied. Only the stronger skiers will exert

sufficient force to fell and reduction in the rate throttle is applied.

The Numbers Skier’s Perspective

Summary - Letters / Numbers / “+”

ZO PULL - A / B / C – NORMAL

JUMP With Version R,

there are only 3

timing segments

52m, 82m, 41m

JUMP POINTS

• Power Factor

• 41 Meter Segment Adder

• Jump letter Select

• Cheating - Mapping wrong intentionally, but it doesn’t

work like they think.

• Cheating - Using unbalanced segments to enhance

swing

• JUDGE – does the system beep when the Tow PYLON

is in line with the timing course entrance?

POWER FACTOR

• The Power Factor raises or lowers the Baseline speed.

• The lower the number the slower the boat enters the course.

• The Power Factor adjustment ranges from “0 to 15”

• At PF 9 – the boat will enter the course at speed. PF > 9 boat will

enter the course faster that set speed. PF < 9 boat will enter the

course slower than set speed.

• For 5.7 Liter Boats – start with PF of 6 or 7

• For 6.0 Liter Boats – start with PF of 4 or 5

POWER FACTOR

HOWEVER!!!!

• PF is also influenced by the letter setting.

• With Letter "A" there is NO baseline speed depression. The boat

will always enter the course at set speed - regardless of PF

number

• AS the letter increases, the set baseline speed will be decreased

(depressed)

• The HIGHER the Letter the more baseline speed is depressed for

any given power factor

• Max baseline depression occurs with letter "T" at Power Factor 4

• With Power Factor at 3 and below, baseline speed will NOT be

further depressed - rather adjustment is made to the ramp rate for

the letter

Power Factor Examples

41 Meter Segment ADDER

• Raises the speed in the 41 meter segment AS NEEDED -

ONLY to compensate for lower powered boats

• Range is from 0 to 9

• Start at “0” and raise as necessary to achieve actual times

• Will not lower the speed in the 41 meter segment. IF speed

is too fast in 41 meter segment, adjustments need to be

made to lower the letter or adjust the power factor

SHORTCUT - to get to JUMP LETTER screen

PUSH & Hold SELECT button

on the “LETTER” until the

Letter – Weight and Distance

tool appears.

Jump Letter Charts – are available for Officials

TRICKS

Background MENU

• What’s all this STUFF in the BACKGROUND???

• There are 4 Background Menus

– SCREEN

– SET

– MAP

– WHO

To get to BACKGROUND MENUs

Press and

HOLD

SCRN SET

MAP WHO

SCREENS

TWO SCREENS

• RECREATIONAL mode

• TOURNAMENT mode

Make certain the driver is using the TOURNAMENT screen.

Pulling an event in RECREATIONAL mode for ANY reason is

NOT permitted!

Examples of Tournament &

Recreational Screens

Tournament > Slalom Example

Recreational > Slalom Example

Tournament > Jump Example

Recreational > Jump Example

Tournament > Trick Example

Recreational > Trick Example

Other SCREENS

SCREEN > Diagnostics

GOOD – no faults BAD – 3 faults

ZO Software

Version 102 R

ZO Software

Version 100 R

SCREEN >Timing RECAP

SCREEN >Timing Recap > Slalom

“LATEST” are the current times / “LAST” was the pass before “LATEST”

(HINT – always read LEFT to RIGHT)

SHORTCUT - TIMING RECAP

Use SELECT button to

highlight “Diamond” then use

UP or DOWN button to toggle

between Tournament, Timing,

& Recreational screens

SET 2 screens - scroll down

SET > Jump Letter

SET > Jump Letter

SHORTCUT - JUMP LETTER

PUSH & Hold SELECT button

on the “LETTER” until the

Letter – Weight and Distance

tool appears.

SET > Slalom Wait Timer

SET > Backlight / Contrast Screen Darker or Lighter?

SET > Volume Adjust

SET > METRIC or ENGLISH KPH or MPH ?

SET > Time Zone

SET > River Mode Normally “OFF”

With “RIVER: ON”

“DNRiver / UPRiver” appears in

TRICK – provides speed

adjustment compensation for

water current.

• KEY ENTRY – not used other than to enter a “# key” to switch system over

to a 3 Event system from Wakeboard and vice versa

• CAN Term: – Normally “OFF”. In the “ON” position allows for the

termination of an open CANBUS connection.

• PROP: 4 Blade or 3 Blade – provides different settings when changing a

propeller.

• ENGINE: Allows for initial setup choice of 5.7 Liter or 6 Liter (2 tries ONLY)

SET > Additional Options

TORM = Throttle Over Ride Mode (Ability to apply additional throttle)

3 options:

ALWAYS – Driver can over ride system at any time

OUTSIDE COURSE – Driver can over ride system ONLY outside the course

DISABLED – Driver can NEVER over ride the system (limited to set speed)

SET > TORM

SET > MAP

With initialization all positions are

“Open” and can me mapped as

either slalom or jump. Select “Live

Course Mapping”

SELECT:

•SLALOM - 4 buoy, 6 buoy, or

overlapping 8 buoy course.

•JUMP

MAP > Slalom

Map slalom entrance and exit gate

when the GPS pucks are in line

with the gate buoys.

MAP > Jump

Begin map when PYLON is at the

entrance line to timing course – 52

Meter (1st segment)

End map when PYLON is at the

start of 41 Meter segment (3rd

segment)

MAP - Jump

Map Map MAP @ PYLON

WHO

Provides a way to preset a

person’s settings for reuse

Judge’s Display

A second display is only required

for IWWF slalom and jump for

Titled and Elite events. (IWWF rule

10.07)

World Titled Events

System shown as “Off”

Thank You

Will Bush

willbush@att.net

Elk Grove, California USA

+1 (916) 837-7464

Perfect Pass

Perfect Pass

New Zbox -- A,B,C,1,2,3 with PerfectPass

StarGazer system. Magnets are optional

Perfect Pass

Can map up to 3 slalom courses

Perfect Pass

MAP – slalom course is mapped by idling thru

(into) the entrance gate on each end