From: CANSAS::IN%"Ron_Bolton@engr.usask.ca" "Ron Bolton" 9-NOV-1996 22:49:18.17 To: IN%"David.Steele@sask.usask.ca" CC: Subj: Some text for your consideration Return-path: Received: from skycat.usask.ca by SKISAS.USask.CA (PMDF V4.2-11 #3676) id <01IBNQ5UPAA88WWNLD@SKISAS.USask.CA>; Sat, 9 Nov 1996 22:49:01 GMT Received: from mackenzie.usask.ca (mackenzie.usask.ca) by sask.usask.ca (PMDF V5.0-6 #15020) id <01IBNDKFV7JK8Y6EKF@sask.usask.ca> for David.Steele@sask.usask.ca; Sat, 09 Nov 1996 16:48:54 -0600 (CST) Received: from mordor.USask.Ca. (mordor [128.233.13.8]) by engr.usask.ca (8.7.6/8.6.9) with ESMTP id QAA26931 for ; Sat, 09 Nov 1996 16:47:36 -0600 (CST) Received: from localhost (bolton@localhost) by mordor.USask.Ca. (8.7.6/8.6.9) with SMTP id QAA08861 for ; Sat, 09 Nov 1996 16:46:47 -0600 (CST) Date: Sat, 09 Nov 1996 16:46:46 -0600 (CST) From: Ron Bolton Subject: Some text for your consideration To: David.Steele@sask.usask.ca Message-id: X-Envelope-to: STEELE MIME-version: 1.0 Content-type: TEXT/PLAIN; charset=US-ASCII Content-transfer-encoding: 7BIT X-Sender: bolton@mordor X-Authentication-warning: mordor.USask.Ca.: bolton owned process doing -bs David: For your consideration. I hope that this is (more or less) what you want... Have a good time in Winnipeg. ron. ------------------------------------------------------------------- ***** Numbers refer to proposal from GOZINTA web page ***** 2.2 Video sensor for attitude determination etc. An Attitude Video Camera may be flown to allow determination of the pointing direction of the optics. It may not be necessary to use this hardware as it should be possible to used the CCD imaging data to accomplish the same thing. It is unclear at this time, however, the effects of spectra smearing on the quality of the image to be used for this purpose. As a result the option is being investigated in parallel with investigations from the other teams. The method to be used will follow that of P. Moorhouse during the GEMINI and OEDIPUS missions. The attitude determination is accomplished using a modified Yale Bright Star Catalog. Some of the instrumentation has been used previously and the operating charateristics are known. It should be noted here that the attitude determination is performed after the mission. As a result the data rate needed on the telemetry system is quite high resulting in the need for compression of the video data. An alternative is to perform the attitude determination during the mission. This will result in more complex electronics and a higher cost. 2.4 Data acquisition and telemetry A simplified diagram of the Data Acquisition system is shown below. O -------------> AVC ^ | | | | | | | | | | | | PS | | | | | | | | | V V V I <----------- FW -----------> DC1 | | | | | | | | | V | | | V CCD <-----------+ -------------> | | | | | | | | | | | V | | | | DC2 <-----------+-------------> GPS | | | | | | | | | | | | | | | | V | | | | V ------------> OBDH <------------+-------------- | | | V T-T . . . . . T-R /| / | / | / | / | / | / | / | / | / | / | / | / | V V GPS-B ------> GBDH Key to components: O: Diffraction grating and lens I: Intensifier and lens CCD: CCD AVC: Attitude Video Camera DC1: Data Compression DC2: Data Compression PS: Power Supply System GPS: Global Positioning System GPS-B: GPS Base Station (on ground) FW: FirmWare Electronics (control) T-T: Telemetry transmitter T-R: Telemetry receiver OBDH: On Board Data Handling Electronics GBDH: Ground Based Data Handling (UofS) Some information to note: a) Power supply is low voltage. It supplys power to all blocks except the Optics block. b) Intensifier is low voltage, fixed gain. c) DC1 and DC2 do not have to be the same compression algorithm. d) The GPS system is an Inverted GPS system that requires transmission of data to the GPS base station. e) Uncompressed data rate is approximately 117Mbits/sec. Compression will reduce this to approximately 10Mbits/ sec. f) Depending of the results of ongoing investigation, the Atitude Video Camera may be modified. This will impact the data compression factor needed (i.e., it reduces it) but may increase the complexity of the firmware needed. 3.1.1 Instrument simulator - star database The Attitude Video Camera will be simulated using a custom Graphical User Interface allowing the team to "see" what the Attitude Video Camera is imaging during the course of the mission. Suitable parameters (time of launch, speed, spin rate, field of view) will be included to allow a realistic simulation to be performed. 3.2 Calibration, testing Calibration of the Intensifier, CCD, Attitude video camera will be done using a Low Brightness Source. This will allow accurate determination of performance and characteristics of the hardware. Where possible standard, space-qualified hardware will be used. This allows confidence in the performance of the hardware over the duration of the mission. Preference will be given to Canadian manufacturers if appropriate. 8 Risk analysis The Risk and Reliability analysis of the vehicle will follow standard methods and procedures. The following are areas of concern: a) Launch This depends on the vehicle chosen for the mission. The manufacturer will be consulted about appropriate parameters for the launch. Indications are neither vibration or G forces are a major concern. b) Parachute deployment A standard (for the launch vehicle chosen) parachute deployment system will be used. The parachute will be deployed at high speed, however, resulting in a larger risk associated with this. Contact has been made with researchers familiar with this type of deployment. c) Imaging The optics and imaging devices must survive the launch. As well the optical path must be stable during the mission. d) Electronics The electronics (including power supply) coulde fail due to vibration, G forces, component failure, etc. Full preliminary testing of all aspects of this will be carried out as part of the testing procedure. e) Telemetry The risk involved here is the failure of the telemetry system. This may be partially alleviated by using on-board data storage for storing some of the acquired data. +-------------------- Ron.Bolton@Engr.USask.CA --------------------+ | | | Ronald J. Bolton, Ph.D., P.Eng. | | | | Professor University of Saskatchewan | | Electronic Systems Research Group 57 Campus Drive | | Department of Electrical Engineering Saskatoon, Saskatchewan | | Room 3B03, Engineering Building Canada, S7N 5A9 | | | | Phone: (306) 966-5412 Fax: (306) 966-5407 | +--------------------------------------------------------------------+