Beaglebone robot test drive.

Test drive with new servo motors and additional sensors.

New motors

The motors was changed to servos. The step motors have big disadvantages. 

• They require a lot of power (more than 1.5A) 
• When step motor run at slow speed - it vibrates. And everything that connected to it vibrates. The vibration is very powerful. It can open screws.

And 2 additional ultrasonic sensors was added at the sides. The software is on it's way.

Beaglebone robot. First testing.

Just tested the robot. It will be great. First simple testing for detecting obstacles.

Work in progress

My second bot is getting better.
Already connected and working:

• Step motors with a4988 drivers, 
• DC/DC convertor 12V to 5V, 
• Adafruit 1.8 TFT display (128x160), 
• Maxbotix Ultrasound range finder, 
• Adafruit INA219 Current/Voltage sensor, 
• VCNL4000 IR proximity sensor. 
• USB Wi-fi adapter

Waiting for some connectors to finish it all.
Linux kernel 3.2.33-psp26 (last stable kernel for beaglebone) should be patched for correct framebuffer display.

Driving stepper motor with beaglebone. Part 2

Another robot in project. A few things about driving stepper motors with a4988 drivers.
The board takes about 120-150 mA without driving them and about 1.3 A with motors on. The faster they moves - the current will be lower. With full speed it is about 500 mA.
The stepper motor in stall state can be very hot - I think it is hotter than 60 C. But you can disable the motor in driver control, when it is not active. I disabled them on startup script and enable only when it is needed.
I am using C++ in eclipse with remote gdb from laptop running Ubuntu. The beaglebone using Ubuntu as OS from http://elinux.org/BeagleBoardUbuntu
Note: The current measured from 12 V power supply.

Driving stepper motor with beaglebone

Beaglebone case

The beaglebone case from sparkfun.com.
I can't mount the 4th screw because of SMD resistors that too close to the mount hole.