Crum is a space explorer robot that is able to draw a map of empty space, see the video and you will know what I mean, very cool stuff.
Introduction of the space explorer robot – Crum
[Big Face] built this robot that can draw a map. The body is made of expanded PVC. Its armed with 3 IR sensors and a sonar sensor. He also included an I2C LCD screen, looks cool and very useful when debugging. Crum has the compass module and the wireless link. He has been working on software for the PC end where data from the robot is received and displayed. He has decided to try an occupancy grid approach to mapping. Data from the robot can be used to draw a map but that is as far as it gone at the minute.
This is a picture of the LCD screen in all its glory. He has got the sonar working.
He managed to get the robot to plot an occupancy grid map using the sensors. The screen shot below shows the grid being filled with white cells to represent unoccupied space and black cells to show where objects are located, although he is getting a lot of false or inaccurate readings at the moment from the IR sensors. The IR sensors are very accurate at longer distances, hence the addition of a ultrasonic sensor.
The space explorer robot scans and send data back to the PC. There is also a very basic obstacle avoidance program which basically involves the robot turning for a certain time whenever an obstacle is sensed. The video above shows Crum producing a map utilizing the ultrasonic sensor data as well as the IR sensor data. He has also altered the mapping software slightly so that the shade of grey displayed on the map reflects the probability of an obstacle in that cell (not very clear in the video). Lastly, Functionality has been added to change the scale of the map and the resolution of the occupancy grid.
Parts Used in this project:
- Actuators / output devices: 2 servos
- Control method: Autonomous.
- CPU: ATMEGA32
- Power source: 6V
- Programming language: C
- Sensors / input devices: SRF05 Ultra Sound, 3xSharp IR GP2D12