Clutch Slip Calculation

Clutch Slip Calculation uses 2 Inputs:

1. Engine Speed (RPM)

2. Input Shaft Speed (RPM)

Example.

Engine Speed = 6000

Input Shaft Speed = 5756 RPM

Clutch Slip(%) = Input Shaft Speed - Engine Speed

            Engine Speed

Clutch Slip(%) = -4.06 %

This means the Input Shaft is rotating 4.06% slower than the Engine Speed… i.e 4.06% Clutch Slip.

Drive Slip Calculation

Drive Slip

Given as a percentage of the difference between the speed of the driven wheel compared to the speed of an undriven wheel. The Drive Slip can be both positive and negative.

Drive Slip = (Speed Channel 1 - Speed Channel 2) / Speed Channel 2

which is normally expressed as:

Drive Slip = (Driven wheel speed - undriven wheel speed) / undriven wheel speed

0.0% = The driven and undriven wheels are at the same speed.

+10.0% = The driven wheels are turning 10% faster than the non driven wheels.

-10.0% = The driven wheels are turning 10% slower than the non driven wheels .

Example 1 - Drive Slip settings. Front wheel drive, 4 wheel speed inputs connected.

Drive Speed Front L = DI 1

Drive Speed Front R = DI 2

Undriven Speed Rear L = DI 3

Undriven Speed Rear R = DI 4

The ECU will average the front wheel speed and load this value into the runtime " Front Axle Speed"

The ECU will average the rear wheel speed and load this value into the runtime " Rear Axle Speed"

Driven Speed Channel = Front Axle Speed

Undriven Speed Channel = Rear Axle Speed

Example 2 - Drive Slip Settings. Rear wheel drive, 4 wheel speed inputs connected.

Undriven Speed Front L = DI 1

Undriven Speed Front R = DI 2

Drive Speed Rear L = DI 3

Drive Speed Rear R = DI 4

The ECU will average the front wheel speed and load this value into the runtime " Front Axle Speed"

The ECU will average the rear wheel speed and load this value into the runtime " Rear Axle Speed"

Driven Speed Channel = Rear Axle Speed

Undriven Speed Channel = Front Axle Speed

Turning Slip

The difference between the wheel speeds on the left side of the vehicle and the wheel speeds on the right side of the vehicle. The ECU uses “Front Axle Speed” and “Rear Axle Speed” to calculate this.

ECU calculated values: If sufficient Input Speed channels are selected the ECU can calculate the following addition data.

Front Axle Speed.

The average of either:

1. 1. The Drive Speed Front L and R or
      

   2. The Undriven Speed Front L and R
      

Rear Axle Speed.

The average of either:

1. 1. The Drive Speed Rear L and R or
      

   2. The Undriven Speed Rear L and R
      

Cornering Speed L.

The average of the Speed Front L (driven or undriven) and Speed Rear L (driven or undriven)

Cornering Speed R.

The average of the Speed Front R (driven or undriven) and Speed Rear R (driven or undriven)

NOTE: The ECU will check which speed channels are assigned and use this information to calculate the data. For this to work correctly for example the Speed Front L Driven and Undriven channels can never both be selected.

Gear Management

Gear Management

The first step to proper gear management/detection is a properly scaled and validated speed signal.

Gear Management in Emtron can be detected in various ways.

Fundamentally, gear control and detection are a part of the ECU functions.

Several channels are linked to the gear functions that can be viewed, logged, and used as active channels :

Gear Position (RPM/Speed) Setup

Speed Lockout

Gear Detection Ratio Calculation stops when the speed fall below this value.

0 = OFF

Typical: 2-5.

Default Gear

Default gear for Gear Detection Ratio Calculation.

Gear Valid Time

Typical: 10ms

Tolerance

Typical: 10%

Fault Time

Fault Time for Gear Detection Ratio Calculation.

Typical: 1000ms

Clutch Switch Lockout

Gear Ratio Detection Calculation temporary stops when the Clutch Switch is ON i.e. during a gear change.

Gear Position (RPM/Speed) Table

Define the multiplier here to get speed for the ratio calculation to work. IE:

100kph *34 in 5th gear = 3400rpm.

RPM/Speed ratio is also actively calculated in Runtimes

3rd gear engaged shown

Gear Position (Input/Outputshaft)

Gear Ratio (Input/Outputshaft Speed) = Inputshaft Speed Source/ Outputshaft Speed Source

Outputshaft Speed Lockout

Gear Detection Ratio Calculation stops when the Outputshaft speed fall below this value.

0 = OFF

Typical: 2-5.

Default Gear

Default gear for Gear Detection Ratio Calculation.

Gear Valid Time

Typical: 6ms

Tolerance

Typical: 7%

Fault Time

Typical: 10ms

Gear Position (Input/Outputshaft Speed) Table

Define the transmission ratios the ECU should expect for calculating gears via Input/Outputshaft speed correlation

Actual Gear Ratio (Input/Outputshaft) can be validated actively calculated in Runtimes

3rd gear engaged shown