Into Robotics ROS, Robots and Stuff Tue, 19 Jun 2018 10:25:38 +0000 en-US hourly 1 Into Robotics 32 32 New ToF Breakout Board with VL53L1X Distance Sensor and a Measurement Range Between 4 cm and 4 m Tue, 19 Jun 2018 10:25:38 +0000 Read more →]]> Breakout Board with VL53L1X Distance Sensor

Breakout Board with VL53L1X Distance Sensor

This new breakout board from Sparkfun has a 1-millimeter resolution and around +/-5mm accuracy – which is good if you want to use the sensor to detect objects or create maps.

The sensor emits a class 1 IR laser (940 nm) which theoretically is safe even for long-term intentionally viewing.

The I2C interface can be used with both a microcontroller (Arduino) or a single board computer (Raspberry Pi). If you use Arduino, you have the Sparkfun VL53L1X Arduino library (less work and more time for you).

What I do not like is the operating voltage which should be between 2.6V and 3.5V. If I want to power it directly from Arduino or Raspberry Pi is ok. Otherwise, I need a 3.3V power supply module or a 5V to 3.3V level shifter.

Theoretically, a ToF module can be used outside with the risk of lower performance. Unfortunately, Sparkfun says nothing about using this sensor outside.

]]> 0
Which Is The Best ROS Ready Robot Arms Under $1000? Mon, 18 Jun 2018 09:04:16 +0000 Read more →]]> I have this robotic arm with 6-axis and very cheap servo motors. When I bought it, I did not think I would use it to who knows what applications. I buy it because is cheap and I can control it with an Arduino Mega and ROS.

The problem is that I want to build a robotic arm capable to identify objects (like an apple or a pear), to pick the fruit from a tree, and put it in a basket near the robotic arm. For these operations, I need an arm with a relatively solid structure and some powerful servo motors. In conclusion, the kit I have is not helping me.

The second plan is to buy a ROS ready robotic arm with servo motors that can handle a weight around 200 grams. Because it is a personal project with a limited budget (maximum $ 1000), I searched for and found the following three robotic arms that would fit my project.

The first option is a PhantomX robotic arm with 4 degree-of-freedom and a gripper with a rated holding strength of up to 500g, while the wrist itself can lift up to 250g horizontally.

The second option is also a PhantomX arm that can handle the same weight as the first one. But it comes in addition with 5 degrees of freedom, a greater range of action and up to 300 degrees of motion.

The third option is the most expensive and I may have the surprise not to receive it in the next few months when I need it. It’s about Niryo One. For now, the arm can only be pre-ordered. The combination of Raspberry Pi, Arduino, ROS, parts that can be printed with a 3D printer – attracts me a lot.

]]> 1
YDLIDAR F4 and G4 Tue, 17 Apr 2018 08:36:46 +0000 Read more →]]>  YDLIDAR Lidar F4 PRO


YDLIDAR F4 and G4 are two LIDAR (Light Detection and Ranging) sensors for environmental scanning, SLAM application… in other words, the sensors are designed for use in robot navigation.

The price range is $259.00 for F4 and $419.00 for G4. Both sensors are in direct competition with RPLidar A1M8(~$219.00) or RPLIDAR A2M6 (~$600.00).

I scan a little bit the specifications to see what is good and bad with these sensors:
the good

  • 12m scanning range (F4) and 16m scanning range(G4) – enough for autonomous robots in agriculture or construction fields;
  • both sensors include a safe low power infrared transmitter conforms to the FDA safety standard of Class 1 laser. This means that is safe to work with these sensors, the human eye is not affected;
  • only F4 uses a USB connection with a computer;
  • only F4 has complete drivers, supporting Windows, Android, ROS, and Linux system;

the bad

  • I try to find more information about who is the manufacturer. Their site is not completed and some links don’t work. The link to the Contact page will redirect you to something that can be called “About us”, while “About ydlidar” redirect to a 404 page. This could be interpreted as small details, but one question came into my mind – how this manufacturer will provide support and documentation for these sensors if they can not solve their own site problems?
]]> 2
An ultrasonic sensor for dirty applications Sun, 08 Apr 2018 10:58:45 +0000 Read more →]]> 5V Waterproof Ultrasonic Module

5V Waterproof Ultrasonic Module

Now I build a 4WD outdoor robot and I was still thinking how to mount the Maxbotix’s ultrasonic sensors so that I don’t have problems with the dust and any other dirty things. Luckily, I discovered this waterproof sensor.

But there are some negative aspects. The sensor is blind for the first 25 centimeters and in many cases I have to deal with obstacles that may appear right in front of the robot (the wind pushes the tree branch in front of the robot).

As a positive side, the sensor is Arduino compatible and is working with 5V. The maximum range of the sensor is 4.5m, but some users seem to have some issue with the maximum distance. For me, a range of maximum 2 meters is much more than I would need. So, I should not worry about the maxim range.

Other important specifications:

  • resolution: 0.5cm;
  • it detects an obstacle at an angle less than 50 degrees;
  • acoustic emission frequency: 40khz;
  • pins: + 5V, Trig (control side) RX, Echo (the receiver) TX,
    GND (negative);

Otherwise, the sensor price is $14.99 without the cost of shipping.

]]> 0
If you don’t have sensors … Fri, 06 Apr 2018 08:13:12 +0000 Read more →]]> use your smartphone to give your robot senses, so it can see where it’s going. Almost any smartphone – even a $30 device – is like a box with sensors. All these sensors can be used for a robot. A sensor like a camera to capture images, the accelerometer and gyro to drive the robot, and the pressure and proximity sensors for any other application.

Husarion, the company behind CORE2, has been developing an Android application that makes available the smartphone sensor readings through a ROS node.

The application is called hNode and creates a network between the smartphone, the robot, a laptop with ROS and the Husarion cloud.

I’m not sure, but to work in this way, most probably the robot should use the CORE2-ROS (running ROS) controller. More details here.

]]> 0