Constrains
Due to the complexity of the project, the constraints were
divided in two parts: general and technical constraints.
I. General Constrains
- Cost:
- Buy the equipment from our pockets The equipment is expensive (e.g. COGNEX Camera).
- Insufficient knowledge:
- Documentation not complete. This issue forces us to research and find any information related to past projects.
- Time:
- Professor Consultation only four hours per week.
- Every minute counts because of the complexity and the different objectives of the project
- Time in repairing components was excessive
- Room Space:
- The limited working space and material was a key factor during the design process. The professor assigned a room by the end of November 2002.
II. Technical Constrains
- Voice Recognition Module:
- The new version of the voice recognition module was not compatible with the program developed by the old Capstone group.
- The processor has a space memory limitation and only holds a maximum of four (4) programs of 500KB of memory, which means we had to limit the programs in accordance to these parameters.
- The system only recognizes a voice in absolute silence.
- Tends to damage itself very easily because of static.
- OOPIC Processor:
- The mechanical parts and servomotors of the head were not properly aligned.
- The OOPIC processor and the Head had to be physically connected because there where given to us separately, without any interconnections between them.
- To establish communication between the Head and the EYEBOT all programs had to be modified to receive and send data through Digital Port instead of the serial port.
- Three (3) servomotors of the head were damage.
- Limited memory for object declaration and variable declaration.
- Capacity:
- 87 bytes for objects
- 96 bytes for variables
- Used:
- 38 bytes for objects
- 26.5 bytes for variables
- Mechanical Constrains:
- The Robot had to be reduced in size in order for it to fit through a door. Its measurements were limited to 36 inches or less.
- The DC motors located in the arms are susceptible for braking easily if used frequently.
- The servo motors of the base don’t have encoders, which means that when switch to auto the EYEBOT have the limitation of not knowing the location of the Robot in given time.
- There were no limit in the rotation of the shoulder motors; This rotation could damage the cables and motors located in the arms.
- The electrical wiring of the Robot was not properly organized.
- Obstacle Avoidance:
- The initial proposed sonar system module (5-120) was very sensitive to static with a limited range of detection. In addition, the servomotors have little precision and cover only 90° around.
- When the batteries of the Robot are disconnected the speed controls loses it’s programming.
- Vision COGNEX Camera:
- Time needed for testing the COGNEX Vision System. We suggested purchasing the system since summer and the university made the order in October 2, 2002.
- The camera arrived on October 30, 2002 without any lens unit.
- The camera was tested without the lenses with very poor results captured.
- The lens unit arrived the 1st week of January and testing began at that time. In the test was found out that the camera has no capabilities to accomplish the proposed COGNEX camera objectives.
