wheelchair is guided by voice commandslll
DESCRIPTION
it's a small Mechatronics Project which includes Programming , design. mechanic and electrical circuitsTRANSCRIPT
WHEELCHAIR GUIDED BY VOICE COMMANDS
Team Members :
Majd Khaleel
Sa’ed Daraghmeh
Alaa Dweekat
Supervised By :
Dr. Aiman Al-Sharea Dr.Nathir Rawashdeh
AIM OF THE PROJECT
To control the movement of a manual wheelchair by means of human voice, it helps disabled and elderly persons, since it does not need any body stress, and just depends on what disabled person says.
OUTLINES
Block Diagram. Parts of The Project Speech Recognition Circuit. Drive Unit. Interfacing Circuit. Conclusion.
Block Diagram. Parts of The Project. Speech Recognition Circuit. Drive Unit. Interfacing Circuit. Conclusion.
BLOCK DIAGRAM
Block Diagram. Parts of The Project Speech Recognition Circuit. Drive Unit. Interfacing Circuit. Conclusion.
PARTS OF THE PROJECT
Wheelchair. SRC. PIC16F877A. Two DC geared motors. 12V-Battery (For motors). 9V-Battery (For SRC & PIC microcontroller). 4 Relays. Joystick. Microphone. Belts.
Parts of The Project Block Diagram. Speech Recognition Circuit. Drive Unit. Interfacing Circuit. Conclusion.
SPEECH RECOGNITION CIRCUIT
SPEECH RECOGNITION CIRCUIT
This circuit is trained to recognize definite required words, and it can be programmed in any spoken language, and even non spoken languages.
The heart of the circuit is the HM2007 Speech Recognition Integrated Circuit.
This I.C. can provide two methods for recognizing a WLEN pin on the main circuit board selects either the 0.96 second word length (40 word) or the 1.92 second word length (20 word).
SPEECH RECOGNITION CIRCUIT
HM2007 pin diagram
SPEECH RECOGNITION CIRCUIT
The HM2007 stores the "trained" word patterns used for recognition in external memory.
Speech recognition is classified into two categories, speaker dependent and speaker independent.
This chip has two operational modes: Manual mode and CPU mode.
SPEECH RECOGNITION CIRCUIT
HM2007 pin diagram
SPEECH RECOGNITION CIRCUITSRC CONSTRUCTION
SPEECH RECOGNITION CIRCUITSRC CONSTRUCTION
SPEECH RECOGNITION CIRCUITTRAINING THE KIT:
SPEECH RECOGNITION CIRCUIT
Testing :When repeating a trained word into the
microphone. The number of the word should be displayed on the digital display.
Clearing the memory :To erase a single word space press the
number of the word you want to clear, then press the "*“ (clear) key.
To erase all the words in the RAM memory (Training) press "99" on the keypad then press the "*" (clear) key.
Parts of The Project Block Diagram. Speech Recognition Circuit. Drive Unit. Interfacing Circuit. Conclusion.
DRIVE UNIT
Drive Unit consists of two main parts are :
I. Two geared DC series motors.II. Transmission unit.
Belt
DRIVE UNIT Why a DC Series Motor Was Chosen?
Very high speed at no load
High torque at low speed
DRIVE UNITIn series motor the flux (Ф) is a function of armature current ( Ia), and it is proportional to (Ia).
DRIVE UNIT
we use two motors in which every motor is attached to its own wheel and this allow us to move the chair in different direction as shown below :
DirectionRight motorLeft motor
ForwardON ( CW )ON ( CW )
BackwardON ( CCW )ON ( CCW )
RightOFFON ( CW )
LeftON ( CW )OFF
DRIVE UNIT
Gearbox We use the gearbox to reduce the speed of
the motor and increase its torque.
DRIVE UNIT
We use helical gear, because The load in helical gear is distributed over several teeth.
Gearbox ratio equal 0.08
Velocity of the motor 4000 rpm using the gearbox become 320 rpm .
DRIVE UNITTransmission Unit
The belt used to transmit power from one shaft to another by means of pulleys which rotate at same speed. The amount of power transmitted depends upon the following factors:
I. The velocity of the belt.II. The tension under which the belt is placed on
the pulleys.III.The arc of contact between the belt and the
smaller pulley.IV.The condition under which the belt is used.
DRIVE UNIT
There are many types of belts :
Flat belt Circular belt V-belt
DRIVE UNIT
We use V-belt because it is mostly used in the factories and workshops.
The V-belt has a positive drive because the slip between the belt and the pulley groove is negligible. The power transmitted by V-belt is more than that of the flat belt for the same coefficient of friction.
Parts of The Project Block Diagram. Speech Recognition Circuit. Drive Unit. Interfacing Circuit. Conclusion.
INTERFACING CIRCUIT
INTERFACING CIRCUIT
SRC
Joystick+
- +
-
INTERFACING CIRCUIT
SRC
Joystick
+
-
+
-
INTERFACING CIRCUIT
DirectionLeft MotorRight Motor
Transistor 1Transistor 2Transistor 3Transistor 4
None0000
Forward1010
Reverse0101
Right1000
Left0010
INTERFACING CIRCUIT
Voice
NO NO NO
YES
NO NO
Parts of The Project Block Diagram. Speech Recognition Circuit. Drive Unit. Interfacing Circuit. Conclusion.
CONCLUSION
Speech can be one of the desirable interface means for wheelchairs.
When this project used by disabled person, he will be more comfortable, and self-dependent in his life.
There is possibility to run the chair at different speeds and choose between joystick and voice control methods.
