Frequently Asked Questions
So what can it do?
The rover is programmable, so the user can decide what it should do!How does Rover1 get up a step?
What is the biggest step it can climb?
The largest step that it can climb is about 7 inches. In the pictures and videos on this site, the rover is climbing a step that is 6 inches high. The height of the omni-wheels is variable to allow the rover to climb steps of different sizes.
Can the rover fall over?
Yes, but you have to be trying. For example, if you move the boom all the way forward, you can get the rover to fall over. The omni-wheels in the back prevent it from falling backwards. We usually keep the center of mass closer to the rear wheels to prevent accidents.
How do you communicate with the rover?
The rover is controlled over a wireless network using 802.11. The rover has a Compaq iPAQ to provide wireless to serial communication.
What processing is done on the rover?
Each wheel is connected to a daughter board to provide speed control on the wheels at 300hz based on encoders. The daughter boards are connected to the Cerebellum microcontroller, which also controls servo motors and the boom motor. The CMUcam does all of the vision processing. The Cerebellum and CMUcam are both connected to the iPAQ. In addition to providing wireless communication, the iPAQ uses the tracking data from the CMUcam and tells the Cerebellum to move the rover's head servos so that the camera is looking directly at the object being tracked.
How is the rover powered?
The servo motors and the CMUcam are powered by a pair of 6 volt batteries in parallel. The motors and boards are powered by a 12 volts (two 6 volt batteries in series.) The boards really only need 5 volts to run, but they cannot run off the 6 volt supply because when the servo motors move, the voltage drops to a point where the boards don't work correctly.
How long do the batteries last?
The batteries last about an hour and a half.
How does the rover know its location?
Each wheel has an encoder on it and that data is sent to the computer controlling the rover. On that computer, the encoders are integrated so that the rover's position and orientation are known. Additionally, the rover relies on landmarks to move from place to place.
How does it recognize objects?
The Rover tracks objects via their color. See the CMUcam webpage for details on how it can track colors.
Does it do any object recognition or matching on images?
No. Such image processing is prohibitivly expensive, in terms of necessary computing power. Rather, the Rover uses a CMUcam camera to do basic processing, such as tracking of color blobs. Soon CMUcam will also be able to compute histograms, which will increase landmark recognition ability.
What are these "landmarks"?
In our usage, a landmark any brightly colored object that is statically located (that is, that won't move around from day to day). The color of the object just needs to be a color that CMUcam can track. We typically use small plastic cones, of the sort used in school playground activites.
Why use landmarks for teaching paths?
Environments such as the home are highly dynamic; things as simple as moving a chair by a few feet could confuse the Rover, if it were relying on pure dead-reckoning to navigate. By providing static landmarks, the Rover can better determine where it should go, even if other parts of the environment have changed.
Will I have to put special landmarks around my house?
In most circumstances, yes.
What happens if the rover gets lost or has its way blocked?
In many cases, if the rover finds its way blocked by an obstacle, it will try to go around it. If it can't find a way around, the rover will be able to ask you for help. You could then remotely teleoperate the rover around the obstacle, or abort the current mission, or the like.
What sorts of things can the rover do on missions?
The rover can use its CMUcam to take pictures, do time-lapse photography, create panoramas, and detect motion. In a future design, we hope to add some other features such as a thermometer, compass, arm, or light.
Can it vacuum my floor (mow my lawn, etc)?
Sorry, but no.
How much does it cost?
The rover is not currently available commercially. Currently, our cost of production is about $4000 per rover. However, we are confident that commercial costs of manufactoring can be brought under $500.
What age group is it for?
Ages 12 through adult.
Is it a toy?
Yes, the rover is a toy, but it is also an educational and creative tool.
What are the educational aspects of the rover?
The rover will teach people about the type of technology needed for autonomous exploration like that of NASA’s Mars Rover. As the user tries to answer the questions “What can my rover do on its own?” and “When does it need help?” they will learn about the autonomous capabilities and limitations of robots.
The rover can also be used to do scientific experiments, for example, time-lapse photography of a plant growing, or a study of which room in the house is used most often.
What makes the rover different from other robotic toys?
The rover is different from other robotic toys because you get to program it and decide what it should do. Many robotic toys have predefined routines. They do not require creative thought. The rover, on the other hand, allows you to define its daily activities. You think of new challenges and goals for the rover, and then you create the solutions.
Can it do things when I am not around?
Yes. One of our main goals is for the rover to be autonomous. You can schedule missions to run at any time, regardless of whether or not you will be present.
Can someone with no programming knowledge use the rover and design missions?
Yes. The user interface is designed so that no previous knowledge is required.
What else do I need to be able to use the rover?
You will need a computer to run the rover’s interface software and a wireless networking card.
When will the rover be available?
We are planning to release the Personal Rover in 2004 in conjunction with the launch of NASA’s Mars Rover Project.
Can my kids or I take a Trikebot class?
We hope to offer the Robotic Autonomy course in 10 to 15 locations next year. We are currently seeking funding.
This project looks really interesting; how can I help?
If you are interested in funding the Personal Rover Project, please contact Illah Nourbakhsh at firstname.lastname@example.org.