Let's Make Robots!

## Update: Added some pictures from the mechanical prototype ##

This is the Berliner. A small Start Here 2.0 robot that is intended to live in Berlin at the Campus Party's LMR place and make fun with the geeks and nerds out there.

The Making-Of

Here some first impressions. 

Yesterday I managed to let a little 1000mAh 7.4V LiPo first blew up the servo and then the H-bridge. White smoke.

So before continuing this robot a electricity tableau with a fuse and a voltage regulator had to be soldered.

Then I went on to outline the control software. You see the motor and the steering process. And the control with the event-mappings. There is a finite state machine for the motor and the steering.

The Berliner makes a forward left turn when the motor is in state forward and the steering is in state left and so forth.

The wheels are taken from the Chaot and reused. One large axle for the front wheels.

One servo for the steering and a continuous servo for the forward and backward move.

One possible approach to get to the final solution is via prototype. Here is this robot as a cardboard prototype.

The electronics of the steering and thrust are added to the prototype.

More to come. Mechanics, Sensorix, Software and Bling-Bling.

 


Further Readings

NEW V3 Arduino Motor controller Shield L298N 2 motors
   "The Arduino Motor controller Shield is based on L298N chipset, which is a high voltage (46V max), high current (2A per phrase) dual full-bridge driver, that can control two motors simultaneously."

Selecting the proper battery for your robot
   "Motors are much more suited to AA, AAA, D or C or even battery packs that are manufactured to a specific voltage and configuration"

A Bit About Batteries
   "Ampere-hour (Ah): This measures the total amount of energy available from a battery before its charge is used up. In small batteries this is generally given in thousandths of an amp. (i.e. milliampere-hours or mAh)"

The CIP Method
   Component- and Model-Based Construction of Embedded Systems

 

Appendix A: Motor Shield Settings

Motor voltage is 12V-16V

This case can only be extended through the motor drive board and the VEX GND terminals to the two power supply to the motor, motor-driven expansion of the board at this time 5V logic voltage converter circuit can work properly. In this case the motor-driven expansion board is set to:

  • VLO:ON,Board need to motor drive circuit is extended
  • VLC:OFF,Not with Arduino's 5V pin connection, security isolation
  • VM:VEX, Extended through the motor drive board VEX / GND terminal for the motor to provide drive voltage


These settings because VLC has not Arduino's 5V pin expansion board with the motor connected 5V logic voltage, so we need any additional power supply for the Arduino (via USB cable or external power supply), mainly for security isolation Consideration, especially in the VEX relatively high voltage on the case.

 

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
Gabriel_f's picture

The control software I see there, what is it? Something homemade?

NilsB's picture

It is a tool called CIP. With this tool it is possible to model the state machines and then generate C-code from the model. More information here

This tool was initially created at the Swiss Federal Institute of Technology in Zurich. It is now under further developed by these guys.

It is not the kind of visual flow-chart programming (like this or this) that one finds on this site from time to time. It is state machine programming. States and transitions, events and actions, inports and outports.

Maxhirez's picture

You can't kill the Chaot!

NilsB's picture

First I thought: You are right. I shall not kill the Chaot. It still works... and was a lot of work to make.

Second I thought: Stop. I can kill the Chaot. It has fulfilled it's purpose in life and therefore has reached end-of-life.

I am a robot maker - not a robot keeper (Quote: Mogul). 

 

 

merser's picture

I love the visual encoders but I don't see a jam donut anywhere : D
Might need to keep the rpms down I can only count so fast.

Maxhirez's picture
Way to represent us Arduinophiles! Can't wait to see it done.