Home | Rates | Small Business Server | Tech Stuff | Contact Kimber | Referrals

 

KimBot 1 (v1.6)

YouTube Video

 

Video of v1.2


Project Overview:

KimBot 1 is a Radio-Controlled car that has an onboard computer that expands its feature. The Computer is a Parallax Basic Stamp 2, and is programmed in PBasic.The Car used is the Grasshopper RC Car, with the included forward/reverse electronic speed control, and standard Futaba servos. The user controls the car via a 5 channel 2.5Ghz Radio, of which 3 channels are used. Channel 1 is forward/reverse, 2 is for steering and 3 is for the mode selector.


KimBot 1 Primary features:


Automatic Drive Mode

Assisted Drive Mode

Computer Off Mode

Low cost (Under $400)

One Sensor


Main Program

Computer-off Mode
When the user has selected computer off mode, the data from the radio is sent directly to the servo and speed control, without any additional processing. The Ping sensor is not active, and the user must reboot the car to return to computer mode.
To enter computer off mode, the user holds the push-button wile turning the car on, or resetting the computer. The program checks the state of the push-button at startup only.

 


Program 1: Computer-Assisted Drive Mode

The user selects assisted drive mode to help control the car better when objects are close, or the vehicle is traveling at a high rate of speed.

1. Computer reads pulse from the radio
2. If the user has selected reverse mode, then the reverse is initialized, so the user will not have to do a double back on the stick to reverse.
3. Based on data from the radio, the ping sensor will be turned into the turn to read ahead of the vehicle.
4. Data is read from the ping sensor to detect objects in front of it, and if there is no data from the sensor, the programs defaults to an error mode, stops, and beeps high to low. If an object is detected in fron of the vehicle, wile the user control is at max forward speed, then the computer will govern the forward speed, slower and slower until it stopps, in front of the object. If the user uses a slower mode, then the vehicle will roll up the object.
5. if an object is detected in front of the vehicle that is less than 15, and the user has the throttle at max, then the car trys to break before colliding with an object.
6. If the user has instructed max forward speed, then the stering range is limited, to help prevent overstoring.
7. if no errors have occurred, and there is not any objects detected in front of the vehicle, then the car will move exactly as instructed by the user.
8. The computer reads channel 3 to see if the program mode has changed.


Program 2: Automatic Drive Mode

When the user has selected this mode the vehicle will scan the room, and move into the most open space. If the vehicle has gotten too close to an object, then it will try to back-away from the object, and resume its forward travel into its perception of open space.

1. Operate sensor in scanning motion, and record 3 distances into memory. If no data is received from the sensor then default to error mode.
2. Set forward speed based on reading from center ping.
3. Close object detection, back away if an object is too close in front or on the sides of the vehicle. If object of less then 15 will trip, will reverse to 30
4. If no close objects are detected, then the measurements are comapired, and the vehicle moves in the direction of the most space.
5. If the car is traveling at a low rate of speed, then the turn is increased.
6. The computer reads channel 3 to see if the program mode has changed.
 


Under the hood

This image shows KimBot1 with the top removed. It has a very simple design which uses off-the-shelf components available from Parallax and your local hobby store.

 

Approximate Costs:
Grasshopper RC Car w/ speed control $ 90
Ping Sensor w/ Bracket and Servo $ 50
Parallax Homework Board (BS2) $ 90
3x ServoPal (Servo Driver ICs) $ 36
2.4Ghz Digital 5Ch Radio Controller $100

Total Cost: $366

 


Electronics Diagram:


Source Code:

Download: KimBot1_ v1.6.03.bs2

Code Language: Parallax PBasic

 


KimBot Credits:

Designed and Built by: Kimber Hall.

Date Started: 1/10/2009

Date Completed: 2/20/2009

Build Time: Approximately 120Hhrs (Including 40 hours to learn Basic Programming Language)

CPU/Microcontroller: Parallax Basic Stamp 2 (Homework Board)

RC Car: Tamiya Grasshopper

 

Copyright 2009: Kimber L. Hall, All Rights Reserved.

 

 

 

Buckley says: You are visitor 

Hit Counter

Copyright 2009 KimberLand Technology Services. All rights reserved.

Last updated: 12/27/2014 04:57:33 PM -0800 | http://www.coldnet.net | Contact Form | Web-Mail Server