Trinibot - a tiny desktop research robot based on ROS

ROS Projects
1

Hi ROS Community,

I started a year and half ago building a ROS enabled tiny robot that costs a quarter of other equivalent robots and that has all the goodies for mobile robotics research right here on my desk.

Besides the usual interruptions and a ton of lessons learnt with low cost hardware, I’m proud to share my results with you, Trinibot V2.0!

TRINIBOT_V2_wm
Features_wm
IMG_4552_watermark
Map-building

Here’s what she has:

  • Quad core RPi3 running ROS Kinetic on Ubuntu Mate 16.04
  • Softkinetic DS525 Time of Flight - 0.15 to 1m @ 320x240 with a 720p RGB camera
  • Filtered IMU and magnetometer
  • Temperature and humidity sensors.
  • In-built 3.6Ah 12V rechargeable battery
  • WiFi and Bluetooth
  • Additional USB port and DC 5V socket for peripherals
  • 8 channel 12 bit ADC for analog sensors
  • A joystick for some interaction
  • A 8x8 RGB panel to generate markers and bitmaps
  • Differential wheel rate control from 1 to 10cm/sec and 0.2 to 1.57 deg/sec with odometry
  • Two additional motors (open-loop) for a robot arm or other actuation
  • Can be ported to other robot differential wheel chassis with DC servos upto 12V 1A.
  • Develop and test while charging!

ROS functionality (so far)

  • Full TF tree
  • Sensor messages
  • GMapping
  • EKF localization

She runs for about 2 hrs with stops and constant sensor streams over wifi. I still need to redefine the covariances for the various sensors (and a lot of other tests of the entire stack).

The next steps are:
URDF
Navigation stack
Interactive functionality

Keen to hear thoughts, questions and critique that will make Trinibot awesome and community friendly!

Cheers,

Kesh

4 Likes
2

Looks like the depth camera is no longer available. A comment on Amazon said Sony bought Softkinetic and took the cameras off the market. They may be only selling OEM units to include in commercial projects.

3

Indeed the DS525 went out of production last month! :frowning: I picked it up last year and it was a big disappointment because the camera was well made. In any case I have 4 spare so I’ll survive :+1:

I’m considering moving to a x86 board with USB3 at some point. Need to find a nice RGBD camera option.

4

This seems like a nice robot. I generally prefer larger bots, but as I’m now living in a motorhome I’m going to have to get used to smaller ones.

The description sounds like this would be useful. I would have added an external I2C port on the controller in order to connect to new low-level sensors without having to work through the USB port.

You were able to put a lot of robot into a small package.

5

I’ve been looking at RGBD cameras so was disappointed to see this one discontinued.

6

Thanks @DangerousThing, I do have an I2C port that can be exposed. Any specific sensors you have in mind? I can provide a data and mechanical interface to mount these sensors.

7

You’re welcome. I tend to buy odd sensors from Sparkfun or Adafruit.
Sparkfun has a “standard” that can be used for I2C sensors. However,
since most of the sensors that I use have their own quirks I mostly just
wire things myself. Most of them use either 5v or 3.3v. Adafruit is
usually better at supporting a wider range of voltages by putting
voltage regulation on the sensor boards.

I use these companies so that I can avoid having to deal with very small
surface-mount components and have access to some components that would
be difficult to get or use. Plus I’m better at software than hardware. :slight_smile: