meem5750 final project final report - sites at penn...

Michigan Technological University

MEEM 5750 Distributed Embedded Control Systems

Final Project – Final Report

Embedded Control System Development

For A Configurable Hybrid Vehicle by Using Model Based Design

Poowanart Poramapojana

April 28, 2011

Project Summary

The major tasks of the final project are to design a control system of the configurable hybrid vehicle.

Then the control designed was validated by the simulation for each sub‐model. To validate the control

system, after complete the simulation process, the control model was created by the MotoHawk

program and uploaded it in to the MotoTron ECU for testing output signals. Seven sub models were

design to execute input signals: a driving mode model, two look‐up tables for blending factor, a throttle

request model, an engine start – stop model, an engine state model, and E‐motor start – stop model and

a stepper motor driving model. The control logic of input and output signals for each sub‐model is

provided by this class. With appropriate combined input signals, the control model was validated. The

results show that the control model was successful development. It can provide correct output signals.

Developed Sub‐Model

1. Look‐up table for the engine and the E‐motor blending factor

The engine and the motor blending factor are adjusted. At high speed, the blending factors are

reduced to zero in order to reduce the usage of the electric energy. When the vehicle operates at

high speed, the engine will be operating at high efficiency also. There will have some extra energy

that is not use so the battery can be recharged.

Adjusted Engine Blending Factor as a function of the accelerator pedal position and the vehicle speed

Adjusted E‐motor Blending Factor as a function of the accelerator pedal position and the vehicle speed

2. Driving Mode

State of Charge (SOC) was added into the condition for determining the driving mode for low vehicle

speed (vehicle speed < 1 mph). If SOC is less than 40%, the vehicle cannot operate on the electric

motor both the electric solo mode and the blending mode.

Adjusted Truth Table for determining the driving mode

Adjusted Logic for Truth Table to determine the driving mode

CONTENTS

Page

Project Summary

Developed Model

1. Introduction……………………………………………………………………………………………………………………………… 1

2. Objective………………………………………………………………………………………………………………………………..… 1

3. Control Model Design…………………………………………………………………………………………………………….… 2

3.1 Driving Mode Model………………………………………………………………………………………………………… 2

3.2 Look‐up Table for Blending Factor…………………………………………………………………………………… 3

3.3 Throttle Request Model…………………………………………………………………………………………………… 5

3.4 Engine Start – Stop Model………………………………………………………………………………………………… 7

3.5 Engine State Model...……………………………………………………………………………………………………..… 10

3.6 E‐motor Start – Stop Model……………………………………………………………………………………………… 11

3.7 Stepper Motor Driving Model…………………………………………………………………………………………… 13

4. Model for Validation………………………………………………………………………………………………………………… 15

‐ MotoHawk Model…………………………………………………………………………………………………………….… 15

‐ Model for receiving the input signals from sensors ……………………………………………………….….… 16

‐ Model for sending the output signals to actuators……………………………………………………..…….…. 17

‐ Controller Model...………………………………………………………………………………………………………......… 18

5. Results and Discussions……………………………………………………………………………………………………………. 19

5.1 Simulation Results……………………………………………………………………………………………………………….…. 19

5.1.1 Driving Mode Model……………………………………………………………………………………………………… 20

5.1.2 Look‐up Table for Blending Factor…………………………………………………………………………………. 22

5.1.3 Throttle Request Model………………………………………………………………………………………………… 23

5.1.4 Engine Start – Stop Model…………………………………………………………………………………………….. 24

5.1.5 Engine State Model...……………………………………………………………………………………………………. 25

5.1.6 E‐motor Start – Stop Model…………………………………………………………………………………………… 26

5.1.7 Stepper Motor Driving Model……………………………………………………………………………………..… 27

5.2Model Validation…………………………………………………………………………………………………………………….. 29

5.2.1 Calibrated parameters for Reading Input Signals…………………………………………………………… 28

5.2.2 Test the E‐motor Output Signal…………………………………………………………………………………….. 29

5.2.3 Test the Forward and the Reverse Output Signals…………………………………………………………. 29

5.2.4 Test the Engine Kill Output Signal………………………………………………………………………………….. 33

5.2.5 Test the Engine Crank Output Signal……………………………………………………………………………… 34

5.2.6 Test the E‐motor Throttle Request Output Signals………………………………………………………… 34

5.2.7 Test the Sequence of the Stepper Motor Driving Signals…………………………………………….… 37

5.2.8 Test the Engine State Output Signals………………………………………………………………………..…… 38

6. Conclusions…………………………………………………………………………………………………………….……………….. 39

MEEM5750 – Final Report P. Poramapojana P a g e | 1 of 39

1. Introduction

This final report provides a control model design, a model for validation on an ECU and results of the

simulations and the validations. For the control model design, there are seven sub models including in

the controller: a driving mode model, two look‐up table for blending factor, a throttle request model, an

engine start – stop model, an engine state model, and E‐motor start – stop model and a stepper motor

driving model. Required input signals and output signal of the control module is shown in figure 1. Logic

for determining each output signals are shown in each sub models. To illustrate different types of

signals clearly, the input signals to the control module are labeled as green, the output signals of

the control module are labeled as red, and the intermediate signals among sub‐models within the

control module are labeled as blue. With appropriate combined input signals, the model was validated

and the results are shown by screens captured of MotoTune windows.

2. Objective

To develop an embedded control system for a configurable hybrid vehicle by using model – based

design.

Figure 1: Overview of the control system for a configurable hybrid vehicle


3. Control Model Design

3.1 Driving Mode Model

Figure 2 shows a driving mode model for the vehicle controller. The driving modes depend on a motor

on switch, an engine on switch and the vehicle speed. The logic for selecting driving modes is shown in

figure 3.

Figure 2: Driving Mode Model

Figure 3: Truth Table Logic for determining the driving mode


3.2 Look‐up Table for Blending Factor

Both engine and E‐motor blending factors rely on the vehicle speed and the accelerator pedal position

of the vehicle as show in figure 4. Figure 5 and 5 demonstrate the blending factor of the engine and the

E‐motor as a function of the vehicle speed and the accelerator pedal position, respectively. By increasing

the vehicle speed and the accelerator pedal position, the blending factor of the engine is increased but

the blending factor of the E‐motor is decreased.

Figure 4: Look‐up tables for the engine and the E‐motor blending factors


Figure 5: Engine blending factors as a function of

the vehicle speed (column) and the accelerator pedal position (row)

Figure 6: E‐motor blending factors as a function of

the vehicle speed (column) and the accelerator pedal position (row)


3.3 Throttle Request Model

A throttle request model for the engine and the E‐motor are shown in figure 7 and 8. To determine

throttle request value for the engine and the E‐motor, Driving mode is a major factor for consideration.

When the vehicle is operating on the E‐motor only, driving mode 1, the E‐motor throttle request is equal

to the accelerator pedal position and the engine throttle request is equal zero. When the vehicle is

operating on the engine only, driving mode 3, the E‐motor throttle request is equal to zero and the

engine throttle request is equal the accelerator pedal position. For the blending mode, driving mode 2,

the E‐motor throttle request is a function of the accelerator pedal position and the E‐motor blending

factor. For the engine throttle request in the blending mode, an engine state is a major factor to

determine the engine throttle request value. Figure 9 and 10 show logic for the engine and the E‐motor

throttle request.

Figure 7: Throttle request model


Figure 8: Inside the throttle request model

Figure 9: Logic for the E‐motor throttle request


Figure 10: Logic for the engine throttle request

3.4 Engine Start – Stop Model

Engine start – stop model is used for determining the engine kill and the engine start value. Figure 11

and 12 show parameters that use for determining those parameters. Logic for determining the engine

kill, the engine crank manual and the engine auto crank are shown in figure 13, 14 and 15 respectively.

Figure 11: Engine start‐stop model


Figure 12: Inside engine start‐stop subsystem

Figure 13: Engine Kill Logic


Figure 14: Engine Manual Crank Logic

Figure 15: Engine Auto Crank Logic


3.5 Engine State Model

Required inputs for determining the engine states are shown in figure 16. Conditions for determining

the engine states are shown in figure 17.

Figure 16: Engine state logic model

Figure 17: State flow of the engine state logic


3.6 E‐motor Start – Stop Model

E‐motor starts – stop model is used for determining the E‐motor on switch and operating direction of

the E‐motor, forward and reverse direction. Figure 18 and 19 demonstrate required inputs for

determining those parameters. Figure 20 and 21 illustrate logic for determining the E‐motor on switch,

the forward and the reverse direction of the E‐motor respectively.

Figure 18: Subsystem for E‐motor start‐stop model

Figure 19: Inside E‐motor start‐stop subsystem


Figure 20: E‐motor Start – Stop Logic

Figure 21: E‐motor forward and reverse Logic


3.7 Stepper Motor Driving Model

A stepper motor driving model is used to control the throttle position of the engine by rotating clock

wise and counter clock wise. Figure 22 and 23 demonstrate required inputs for determining the rotation

direction of the stepper motor. Stepper Motor Control Logic is shown in figure 23. For model validation,

delay time was added into the logic for each rotating step in order to easily observe the changes from

the current rotating step to the next step.

Figure 22: Stepper motor model

Figure 23: Required input and output for the stepper motor control


Figure 24: Stepper Motor Controlling Logic


4. Model for Validation

A template of the MotoHawk model for the model validation is provided and shown in figure 25. A

developed controller module was added into the MotoHawk as shown in figure 26. Figure 27, 28 and 29

demonstrate models for receiving the input signals from sensors, sending the output signals to actuators

and controller module.

Figure 25: MotoHawk Model for validation

Figure 26: Inside Foreground block


Figure 27: Model for receiving the input signals from sensors


Figure 28: Model for sending the output signals to actuators


Figure 29: Controller Model


5. Results and Discussion

5.1 Simulation Results

Driving mode model

The model was tested three modes when the vehicle speed is less than one mile per hour as shown in

figure 30. Figure 31 show the changing vehicle speed from 0.5 mph to 10 mph (>1 mph). The driving

mode unchanged when the velocity increase.

Look‐up Table for Blending Factor

The look‐up table for the engine and the E‐motor blending factors was tested at low, medium and high

values of the accelerator pedal position and the vehicle speed as shown in figure 32.

Throttle Request Model

The engine and the E‐motor throttle request model was tested with different driving modes. Figure 33

shows a simulation result for the engine. Figure 34 shows a simulation result of the E‐motor.

Engine Start – Stop Model

The engine kill model was tested for a signal output of “False” as shown in figure 35. For the manual

crank and the auto crank logic, the models were tested for signal output of “True” as shown in figure 36

and 37 respectively.

Engine State Model

Figure 39 demonstrates the test condition with constant engine speed and engine on mode (engine kill =

0). A simulation of the test is shown in figure 39.

E‐motor Start – Stop Model

The E‐motor start – stop model was tested for a signal output of “True” as shown in figure 40. For the

forward and the reverse logic, the models were tested for signal output of “False” as shown in figure 41

and 42 respectively.

Stepper Motor Driving Model

The stepper motor driving model was tested with both clockwise and counter clockwise direction. Figure

43 and 44 show output signals for clockwise and counter clockwise direction respectively. Note that the

delay time for each step is 5 seconds.


5.1.1 Driving Mode Model

Figure 30: Simulation results of the driving mode model


Figure 31: Simulation results of the driving mode model

(a) Engine on switch = True, Motor on switch = True and Vehicle speed <1

(b) Vehicle > 1 mph

(a)

(b)


5.1.2 Look‐up Table for Blending Factor

Figure 32: Simulation results of Look‐up tables for engine and E‐motor blending factors


5.1.3 Throttle Request Model

Figure 33: Simulation result for engine throttle request

Figure 34: Simulation result for E‐motor throttle request


5.1.4 Engine Start – Stop Model

Figure 35: Simulation result of Engine kills logic

Figure 36: Simulation result of Manual crank logic

Figure 37: Simulation result of Auto crank logic


5.1.5 Engine State Model

Figure 38: Simulation model for testing the engine state logic

Figure 39: Simulation results of testing the engine state logic


5.1.6 E‐motor Start – Stop Model

Figure 40: Simulation result of E‐motor start logic

Figure 41: Simulation result of E‐motor forward logic

Figure 42: Simulation result of E‐motor reverse logic


5.1.7 Stepper Motor Driving Model

Figure 43: Simulation result of the stepper motor for clock wise direction

(delay 5 seconds for each step)


Figure 44: Simulation result of the stepper motor for counter clockwise direction

(delay 5 seconds for each step)


5.2 Model Validation Results

5.2.1 Input Signals Calibrated parameters

Vehicle speed input signal, the frequency input signal was calibrated from 100 – 290 Hz to 0 – 19 mph.

Average of the engine speed, the frequency input signal was calibrated from 10 – 1000 Hz to 10 – 1000

RPM. The accelerator pedal positon and the throttle position was calibrated counts number of 330 –

1023 to 0 – 100 percent. Gain and offset for the calibration are shown in table 1

Table 1: Input signals calibrated parameters

Signals Gain Offset

Vehicle speed 0.001 ‐10

Engine Average RPM 0.01 0

Throttle Pedal Position (TPS) 0.1443 ‐47.619

Accelerator Pedal Position (APP) 0.1443 ‐47.619

5.2.2 Test the E‐motor Output Signal

The “E‐motor On” output signal was tested for “True” when the driving mode is 2. Figure 45 and 46

demonstrate the results.

Figure 45: E‐motor on = 1 when Driving mode = 2 and E‐motor blending factor = 1 (>0.01)


Figure 46: E‐motor on = 1 when Driving mode = 2 and E‐motor blending factor = 0.50 (>0.01)

5.2.3 Test the Forward and the Reverse Output Signals

Figure 47, 48 and 49 demonstrate the testing results for the forward output signals value of “True”

when the driving mode is of 1, 2 and 3 respectively. Figure 50 demonstrates testing results for the

reverse output signals value of 1


Figure 47: Forward = 1 when Driving Mode = 1 and Forward Switch = 1




Figure 50: Reverse = 1 when Driving Mode = 1 and Reverse Switch = 1


5.2.4 Test the Engine Kill Output Signal

For the figure 51, the engine was not killed when the vehicle operates on the blending mode and both

the engine and the E‐motor blending factor are not zero. When the vehicle operates on the E‐motor solo

mode, the engine is killed. Figure 52 illustrates the engine kill output signal and the vehicle operating

conditions.

Figure 51: Engine kill = 0 when driving mode = 2 and engine blend factor = 0.75

Figure 52: Engine kill = 1 when driving mode = 1 and engine blend factor = 0.00


5.2.5 Test the Engine Crank Output Signal

Figure 54 demonstrate the engine auto crank. The vehicle operates on the driving mode 2 and the E‐

motor blending factor is zero. The engine auto start even the crank switch was not turned on.

Figure 53: Engine crank = 1 when driving mode = 2, crank switch

5.6 Test the E‐motor Throttle Request Output Signals

The output signals of the E‐motor was measured the voltage and its corresponding throttle request. E‐

motor throttle request as a function of the motor voltage is shown in figure 54. For figure 55 to 58, the

controller was tested at the driving mode 2 with different engine and E‐motor blending factor.


Figure 54: E‐motor throttle request as a function of the motor voltage

(after applied the gain and the offset)

Figure 55: E‐motor throttle request = 1 when Driving mode = 2, Engine blend factor =1 and APP = 1.53


Figure 56: E‐motor throttle request = 6 when Driving mode = 2, Engine blend factor =0.5 and APP = 12.9

Figure 57: E‐motor throttle request = 0 when Driving mode = 2, Engine blend factor =0 and APP = 12.9


Figure 58: E‐motor throttle request = 6 when Driving mode = 2, Engine blend factor =0.5 and APP = 12.9

5.7 Test the Sequence of the Stepper Motor Driving Signals

Testing results for the sequence of the stepper motor driving signals is shown in figure 59

Figure 59: LED light is on corresponding to the sequence of the output signals for each rotating step


5.8 Test the Engine State Output Signals

Figure 60 show the engine off (engine state = 1) when the engine kill is 1 and the engine RPM is 0. Figure

61 shows the engine on (engine state = 2) when the engine kill is 0 and the engine RPM is 0. Figure 62

show the engine on (Engine state = 4) when Engine Kill = 0 and Engine RPM >50.

Figure 60: Engine Off (engine state = 1) when Engine Kill = 1 and Engine RPM = 0

Figure 61: Engine Off (engine state = 2) when Engine Kill = 0 and Engine RPM = 0


Figure 62: Engine on (Engine state =4) when Engine Kill = 0 and Engine RPM >50

6. Conclusions

This controller model was successful development. It can provide correct output signals. For the vehicle

controller development, model validation by simulation is needed for testing output signals from each

sub‐model. This process is able to reduce a lot of time for testing with real instruments. In addition, the

simulation can reduce for destroying instruments in case that the model was a wrong design.

There is a minor error at displaying value for the testing E‐motor throttle request. The throttle request

value is a little bit different from the design. The error might come from the setting of the display value,

a number of decimal.

meem5750 final project final report - sites at penn...

Documents