Dual control RC car
Introduction
We have always liked playing with remote controlled (RC) cars, so we decided it would be fun to modify certain aspects of it. This led us to the idea of changing the remote control so that the car responds to different types of input. For our project, we modified the controls for an RC car so that it responds to the tilt of a hand to drive it. By using a two-axis accelerometer to detect hand orientation, we were able to translate those movements into forward, reverse, and turn for the car. An additional control was added to interface with a PS/2 mouse to drive the car as well. A push button was used to switch between the two input types. We also added a recording and playback feature so that we could record a series of movements with the car and play them back at a later time.
High Level Design
Rationale
Simple radio control cars usually come with two joysticks to control the forward/reverse and left/right directions of the car. We thought that it might be fun to change the controls into something that might be a little easier to control, and came up with the idea of just tilting the hand to control the car. After discussing several possible options, we decided that the best way to sense tilt was to use a low-g accelerometer. Low-g accelerometers can sense the force of gravity, and as the sensor turns, the amount of force exerted on the sensor changes, and the output is changed as a result. Since we wanted four directions (forward, back, left, and right), we decided to use a two-axis accelerometer to sense tilt in the x and y directions. Later, we decided to add additional features to our controller such as the ability to use a mouse for input and the ability to record movements at the suggestions of our TAs and professor.
Logical Structure
The basic structure of our project consists of a user input, processing and analysis, and control. No modifications were done to the car. The user input consists of several subcomponents. First, there is the input for the car control. This consists of a mouse as well as a two-axis accelerometer. For the mouse, the button presses correspond to moving the car forward and backwards – left click for forward and right click for backwards. The user moves the mouse left and right to turn the wheels of the car left and right.. An Analog Devices ADXL203 two axis accelerometer was used to sense tilt of the hand and control the car. The user basically tilts the accelerometer in the direction he/she wants to move the car. See figure 1 for details. Another set of inputs is the playback and record buttons. There are two pushbuttons located on our board, one for start/stop record, and start/stop playback. An LED will blink to show that it is in recording mode, and the LED will be on (not blinking) if the controller is in playback mode. The third input set is the toggle to switch between the mouse and accelerometer input. This input is also a pushbutton, and each time the button is pressed, the input is switched.
Link: http://instruct1.cit.cornell.edu/courses/e...page/index.html
Introduction
We have always liked playing with remote controlled (RC) cars, so we decided it would be fun to modify certain aspects of it. This led us to the idea of changing the remote control so that the car responds to different types of input. For our project, we modified the controls for an RC car so that it responds to the tilt of a hand to drive it. By using a two-axis accelerometer to detect hand orientation, we were able to translate those movements into forward, reverse, and turn for the car. An additional control was added to interface with a PS/2 mouse to drive the car as well. A push button was used to switch between the two input types. We also added a recording and playback feature so that we could record a series of movements with the car and play them back at a later time.
High Level Design
Rationale
Simple radio control cars usually come with two joysticks to control the forward/reverse and left/right directions of the car. We thought that it might be fun to change the controls into something that might be a little easier to control, and came up with the idea of just tilting the hand to control the car. After discussing several possible options, we decided that the best way to sense tilt was to use a low-g accelerometer. Low-g accelerometers can sense the force of gravity, and as the sensor turns, the amount of force exerted on the sensor changes, and the output is changed as a result. Since we wanted four directions (forward, back, left, and right), we decided to use a two-axis accelerometer to sense tilt in the x and y directions. Later, we decided to add additional features to our controller such as the ability to use a mouse for input and the ability to record movements at the suggestions of our TAs and professor.
Logical Structure
The basic structure of our project consists of a user input, processing and analysis, and control. No modifications were done to the car. The user input consists of several subcomponents. First, there is the input for the car control. This consists of a mouse as well as a two-axis accelerometer. For the mouse, the button presses correspond to moving the car forward and backwards – left click for forward and right click for backwards. The user moves the mouse left and right to turn the wheels of the car left and right.. An Analog Devices ADXL203 two axis accelerometer was used to sense tilt of the hand and control the car. The user basically tilts the accelerometer in the direction he/she wants to move the car. See figure 1 for details. Another set of inputs is the playback and record buttons. There are two pushbuttons located on our board, one for start/stop record, and start/stop playback. An LED will blink to show that it is in recording mode, and the LED will be on (not blinking) if the controller is in playback mode. The third input set is the toggle to switch between the mouse and accelerometer input. This input is also a pushbutton, and each time the button is pressed, the input is switched.
Link: http://instruct1.cit.cornell.edu/courses/e...page/index.html