Author Topic: Homemade knex robotics building system project  (Read 832 times)

Offline Mister Gears

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Homemade knex robotics building system project
« on: December 10, 2017, 02:59:50 pm »
Hi everyone, recently I found an old topic wich speak about the "robotics building system education set".
And it was said that the price of the set is too expensive for what it's contain, and that it will be cool to made an homemade robotics building system with arduino or rasberry pi.
It give me some ideas and recently an occasion to do this is appeared at school, in the Informatical and Digital Creation lesson.
 Our teachers said that we can made our own group project, and I proposed you know what. In my group we are only 2, but my teammate is the best programmer of our classroom, so the Knex Robotics Building System project has begin  (- :
Here the first images of the electronical scematics, and of what we need in the algorithm (in french, because I’m french, and because i’m too lasy to translate 2 pages in english for the moment^^)

Offline GWorks

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Re: Homemade knex robotics building system project
« Reply #1 on: December 10, 2017, 05:56:38 pm »
This looks pretty promising!
Don't forget that a motor can draw several mA's... if drawn directly from your microchip, the chip will not like that! Best if you switch the motor on/off with a transistor. Speed you can regulate with PWM (Pulse Width Modulation). The Arduino has this on several outputs.
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Offline Mister Gears

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Re: Homemade knex robotics building system project
« Reply #2 on: December 10, 2017, 09:20:40 pm »
Yes I know it, I'll use an H-bridge, because I can control the direction of the motor with it.
Thanks for your advice^^, even though I knew it already.

Offline Mister Gears

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Re: Homemade knex robotics building system project
« Reply #3 on: January 09, 2018, 08:39:51 pm »
I've begin the coding phase 2 weeks ago, and... it's very long.....
First coding program, and the whole electronical schematics circuit coming in... I think 3 weeks
And this time I will translate in english ^^

Offline Mister Gears

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Re: Homemade knex robotics building system project
« Reply #4 on: October 28, 2018, 04:35:02 pm »
After many test (on paper and on computer), I've finally get a theorically functional system (it's the 4th version). And I found a cool name for this : K'nomputer Device. It sound cool ^^
So, basically it was supposed to run like the lego NXT device. But possibilities are really limited, because there is only 4 input socket outlets and 4 output.

So, the current prototype system look  like this:

-Control brick :
Countain : atmega2560 processor ; 20*4 characters lcd screen ; bluetooth phone communication device ; speaker ; control buttons : 1 OK button, 1 selection wheel, 1 bluetooth connection button ; warning led ; bluetooth connection state leds : not connected, connected, ongoing connection ; 20 input/output sockets for modules ; Input/output socket state leds : green for input state (sensors), red for output state (actuators) ; SD card ; Battery control system( countain : attiny84 processor ; 3*3,6v lipo battery ; 3 battery temperature sensors ; Switch on/off transistor ; Power button ; Battery recharching/ power supply socket ; battery voltage sensor ; battery charging state sensor).
How it work :
Step1 : You make your programming code on your phone (with an app made on app inventor especially to make programs, control the brick, and send programs to the brick), you send the program that you want on the brick (with bluetooth), the brick regsitering the program in the SD card.
Step2 : You execute a program already registered on the brick with the buttons on the control panel of the brick or with a phone connected by bluetooth to the brick. Then if all the modules are properly connected to the brick, the program will run itself (You can make a program wich for exemple can interact with your phone : when you rotate the phone, the bot move. But it can run without any outside control) and if the modules aren’t properly connected, the brick will notify on the lcd screen and on an eventualy connected phone the bad connections. (PS : when you connect a module to the brick, it will immediatly identify the modules and notify on the lcd screen and on an evantually connected phone wich is the module having been connected and on wich socket it has been connected)
Step3 : To stop a program you only have to press the power button. It will imediatly ask if you want to stop the proggram and if you confirm, it stop the program and return to the global menu, else it restart the program from the begining.

-Sensor Modules:
Distance sensor
Color sensor
Weight sensor
Magnetic sensor (send signal when a magnetic part stand in front of it)
IR sensor (countain an emmetor led and a sensor led, the 2 leds are one in front of the other one, and when something pass between the 2 leds it send a signal)
Axis speed and position sensor
Inclination and acceleration (x, y, z) sensor
Compass sensor
Binnary sensor multiplier (by 8) (little box upon wich 8 maximum binnary sensors can by connected : like buttons)
Remote sensor (with a special remote)

-Actuator Modules:
Binnary actuator multiplier (by 8) (little box upon wich 8 maximum binnary actuators can by connected : like leds, or classical 3v K’nex battery motors : control only switch state)
K’nex 12v classical controler (control only switch state and direction)
CC motor small size (you can control direction and roation speed) need external battery
CC motor medium size (you can control direction and roation speed) need external battery
CC motor big size (you can control direction and roation speed) need external battery
Brushless motor (a drone motor to build…. Well, flying ball machines ? ^^) need a powerfull 12v external battery
-Special modules :
Mini control brick (like the normal control brick but smaller and with a 16 by 2 lcd screen)
Micro control brick (like the normal control brick but much smaller and without lcd screen, it replaced by leds display)
Radio (low range) Transmitter/Receiver
Radio (long range) Transmitter/Receiver
Inter Brick data sender/receiver (connect a control brick to an other one with wires, you need to connect 2 wire (1 for data from brick 1 to 2, and 1 for data from brick 2 to 1))

If you have any other ideas for a new modules or a suggestion, feel free to tell it in the chat ^^

Offline Mister Gears

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Re: Homemade knex robotics building system project
« Reply #5 on: November 01, 2018, 01:59:38 pm »
The battery controller system schematic is done, if you know how to make it more simple, please tell me ^^