I´ve been quite busy with the motor of this robot and I already started to have some of the results I wanted, but I still couldn´t find a stable setup, after a couple of drifts it starts to lose power as you can see by the end of the movie.
Besides this, I like the way it moves, and I can have some control when it´s drifting, it is now my anti-stress toy!!! :)
I have also made some major updates to the arduino circuit board. As you can see in the photo below, I finally have figured out how to upload code to a custom arduino board, (this post describes everything related to this), added capacitors to the L293D, added pins for the ladyada xbee adapter and also added pins for the sonar sensor.
To upload code, I have to add a switch button, to change the rx / tx wires from the xbee to the ftdi cable :)
The power button connects to the white bit at the left of the power connector
I added this male connectors so that I don´t have to remove the circuit when uploading
This post is a full description of all the building process, the main idea started with the ratbot, and then I found out that I could follow the same concept with a different approach :)
Click the button to read more:
I used this little and cheap car toy, two caster wheels and a plastic tube to build this bot.
I used polymorph to create an inner support to the servo, this way the servo will have an horizontal position which is necessary for this robot.
More side supports were added with polymorph and wood. I guess the servo won´t go anywhere now :)
This is the Arduino based circuit, I´ve assembled all the components on a perfboard. From left to right you see the XBee with 3.3v voltage regulator, L293D motor driver, 5v regulator, Arduino chip, and power connector.
This is the back side of the circuit, a friend told me I was better with wire wrapping technique than his college teacher :)
The circuit fits neatly inside the case
A rat without a tail it is not a rat at all :) ..it was made with polymorph, I consider this material to be the best that I have.
I mounted a micro-servo to hold a little sonar (SFR10). Later I will make this bot autonomous
And this is the final look, for now it will be remote controlled by the G-Remote (Arduino Based Remote Control)
I´ve had several issues with this bot, first the direction was unbalanced, it was always turning to one side and was impossible to control, then the motor gears started to have some missaligment and the motor seemed to spin and to go out of grip with the gears, I tried to solve it but the issue still remains, everytime this happens I have to tweak the chassis, press the motor, and it goes ok for a couple of minutes and then it happens again. I feel that the robot could be a lot faster and more powerful, I will do my best to solve this, If I have success I will create another post with a full description of the workaround :-)
This is a ratbot derivated, faster, cooler, and with more fun! :)
I like pretty much the way it is going until now, but there are still things I want to do. Beside that, I can´t make it move straight in a line, it seems that it is not well balanced.
When finished, I will post details about the building process.