Juhana Leiwo – Marco Torti
Position and movement Direction of acceleration (gravity) Proximity and collision sensing 3-dimensional spatial mapping
Camera vision Heat detection (to recognize humans, for example) Sound sensing (for voice commands and human activity sensing)
Not all possible applications of the robot necessarily need all types of sensors. For a multifunctional robot it could be useful to determine a number of basic senses The price of the robot is critical because the mapping feature is impostant in houses
Data from different sensors can be combined to gain a more reliable representation of the robot's environment and its focus of attention. (For example, compare the camera view image with a projection of the 3d map to determine the robot's pose or the camera image and the heat sensor can establish if something is an object or a living)
With stepped motors and servos, the position of the robot's joints is known by definition. Compact and reasonably priced accelerometers and gyroscopes are commercially available. Using these, the robot can have an accurate sense of balance. Quickly googled link: hp?cPath=36 hp?cPath=36
For proximity and collision sensing there are a number of alternatives. Depending on the application, they can be used alone or as a combination. Ultrasound range measurement, as used in car parking sensors ture=related ture=related Light reflection using LEDs and photocells (or just LEDs, they work as photocells too, see link: re=related ) re=related Touch whiskers mounted on displacement sensors:
The camera vision and 3d mapping can be combined. Structured light triangulation is a simple way of making 3d scans, probably suitable for the ceilbot. It uses a planar (or other shape) laser beam with a variable angle and a camera to record the beam's reflection. One camera would be enough for vision and spatial mapping.
For heat detection, a single infrared heat sensor could be used instead of a heat camera, if no high resolution heat images are needed.
Use many sensors combined or a single sensor for a given purpose? For example, using just a few proximity sensors simplifies wiring and circuitry, but covering the whole robot in them could make it very agile and capable of operating in a tightly packed space.
Where to mount the sensors? For example, mounting the camera on the main body simplifies navigation calculations, but mounting it on the arm enables close viewing and removes the need to calculate which part of the camera image is in fact the robot's own arm. Maybe use two cameras?
What functions (if any) are more important than others? What functions are needed to complete a given task? For example, does a vacuum cleaner robot need a camera, or is a mapping and collision avoiding system enough? What senses are necessary to make a multifunctional robot?
How best to combine the data from different types of sensors so that they support the same operation? Should the robot have separately processed reflexes and planned operating, or should all data be treated with equal attention? What sort of memory structure would the robot have? Should it be able to learn, or should it just rely on preprogrammed atomic actions?
Several structures has been hypotized during the brainstormings Every structure has weaknesses and strengths
STRENGTHS Fast Long arm not needed WEAKNESS The robot can reach just one room
STRENGTHS Can reach several rooms No problems with particular ceilings WEAKNESS Needs a big battery Very slow A lot of gripping points on the ceiling
STRENGTHS Can bring a lot of things WEAKNESS A lot of rails Needs a long arm and/or long telescopic pistons
Is possible a structure with all the strengths of the previous???