Group SD0601

From ECE Department Wiki

Contents 1 Project Title 2 Members 3 Project Description 4 Requirements Capture 5 Main Components 6 Documents 7 Keywords

Project Title

Motorized Transporter

Members

• Forest Mandan
• Wayne Shields
• Chad Heidt
• Paul Overman

Advisor

• Dr. Subbaraya Yuvarajan

Project Description

We are to design and build a motorized transporter that will be used by individuals that have limited capacity to lift objects or bend down. Our project when completed will provide individuals with a cart that will rise up to table top height for easy transfer of an object to the transporter and then lower to allow for easy movement to a location required by the user.

Requirements Capture

• Ability to raise and lower, table that will rise to assist with loading and unloading

• Ease of operation, should not require much time to learn how to operate

• Ability to carry fifty pounds for half an hour or more

• All terrain wheels to travel outdoors and on various surfaces

• Size of approximately 26"x22" for the table top

• Attached control operator that has control for joystick operation, leash control mode and buttons for the lift control up and down

Main Components

Controls

The motorized transporter consists of two independant control options. The first uses a small thumbstick that is similar to those use in a PS2 controller. This control will provide 360 degree movement for the cart. The second control option is what we have dubbed a 'Leash Control'. This control uses two potentiometer connected to our control cable that is connected to the joystick. One potentiometer is used to control the foward movement that depends on how much of the control cable is pulled out of the cart. The second potentiometer measures lateral movement by adjusting as the cable moves from side to side.

Microprocessor

We are using a PIC 16F series microprocessor in our project. We are using the Pulse Width Modulation (PWM) function in the microprocessor to drive our motors. PWM works by varying the length of the signal according to the duty cycle of the waveform. By varying the duty cycle we are able to control how long each motor is turned on or off for. This allows us to control speed, braking, and direction of our motorized cart.

Motors and Motor Drive Circuitry

We are using the RFR1A motor and frame setup that we purchased from Kadtronix. This setup comes with two independant 24 V DC motors. We are going to run them at 12V to lower the speed of the motors and also to reduce power consumption within our transport. The two motors are run by an independant H-bridge that we aquired from STmicroelectronics which will allow our motors to run in both foward and reverse.

Battery and Lift

The battery we have decided to use is a sealed lead acid battery. We went with this because of cost, weight, load characteristics and ease of charging with long battery life. Along with the battery we will design and build a battery charger circuit that will utilize a UC3906 Smart Battery Charger I.C. One of the features that we have decided to build into our cart is the lift table. The table top of our cart will raise and lower to facilitate loading and unloading of whatever the user would like to move, within certain load restrictions. We have determined that the load that our cart will handle should be no more than fifty pounds, which should be more than adequate for most everything we can see being moved with our cart.

Documents

• Requirements Capture Document403
• Options Considered Document403
• Final Document405
• Users Manual405
• Requirements Capture Document405

Keywords

• DC Motor
• Pulse Width Modulation (PWM)
• H-Bridge
• Transporter
• Cart
• Motorized
• Senior Design
• ECE 403
• Joystick
• Leash Control
• Battery Charger
• Lift
• Thumbstick