Date: Mon, 12 Feb 1996 19:27:57 -0600
This Weeks Deliverables : Richard Eddings - 1) Finish Drive and Steering System Design revisions 2) Began Thermal Calculations James Ledbetter - 1) Began Final Power Calculations 2) Started Motor Control Schematics 3) Started CPU Selection Process Brain Pustka - 1) Reviewed Functions, Requirements, and Constraints of structure 2) Compiled Materials List 3) Begin Frame Design Tim Horne - 1) Made final selection on Data Comm System 2) Continue research on obstacle detection methods 3) Begin design on Sensor System 4) Get detailed info on cameras <== didnUt complete Next Weeks Deliverables : Richard Eddings - 1) Complete Thermal Estimates Rover Systems 2) Help with Structure Design James Ledbetter - 1) Final Power Calculations 2) Shot list of CPU Control Systems 3) Functional Power Block Diagram Brain Pustka - 1) Complete Frame Design 2) Short list for Materials Tim Horne - 1) Complete Comm. System Design 2) Complete research on obstacle detection 3) Complete Sensor System Block Diagram and Part ListThe function for each structural component has been looked at to try to match several materials that can fit the needed requirements. The list for each is long but there are some materials that exhibit most requirements. The thermoplastic composites are a family of materials which which will be most utilized. Alluminum alloys also offer great strength and excellent thermal properties for use in the wheels and legs of the vehicle. A completed list will be sent shortly.
The drive motors have been changed to the 2522-838 motor from Maxon. They have been chosen as the drive motors due to the close match in characteristics needed for the rover and the fact that they require little alteration to prepare them for the lunar environment. The steering assembly has been changed also, to a step motor. The configuration and exact motor will be included in next weeks report. The thermal revisions have altered the wheel design slightly. Also, we will try and rely, for the most part, on a passive system to retain the required heat during the lunar night. A thermoelectric cooler will be available, however, to aid in heat storage.
The control system is being redesigned to meet the new requirment of the using Image Processing for obstacle detection. The orginal controller (Z-180) could not preform the necessary computations fast enough to do to be able to detect objects as the rover moved. Both single and multipule processors will be considered for this process.
Power requirements for all rover systems are being gathered and are nearly complete. Operation mode will follow as soon as this list is complete. Exact camera and Control System requirements have not been obtained.
The Data Communications system has been choosen a Motorola Radio Packet Modem (RPM) will used. However, the data rates for this device are currently to slow but are acceptable for the prototype. Higher data rates will be looked into for the actual design.
QUESTION : Is there a detailed communication system design for the lander - earth link. The bandwidth and data rate of this signal will determine what we ( the rover) will be able to sent back. Please contact Tim Horne with this information ASAP. Note : If no information is received we will issuse a spec list for the system.
Mass: 10 kg
Power: 50 W