User Tools

Translations of this page:

Site Tools


en:lesson03

03 Lesson. OrbiCraft Educational Kit’s Assembling

Educational Kit Description and Contents

OrbiCraft Educational Kit (along with Terra Orbital Simulator Set) is the semi-realistic simulation kit designed for schoolchildren and undergraduates’ training on spacecraft design basics.

Educational Kit characteristic feature is its ability to put emphasis on system design of a spacecraft in general with quick achievement of the goal: the functioning model.

The external view for the assembled spacecraft model and orbital simulator set:

OrbiCraft Educational Kit includes:

  • Host Onboard Computer based on Raspberry Pi;
  • Power System, including Battery and Command Unit;
  • Orientation Finding and Stabilization System, including solar sensors, magnetometer, angular rate sensor and reaction wheel;
  • Telemetering radio transmission system;
  • Pay Load (filming camera).

The external view for Educational Kit in packing case:

The external view for Educational Kit’s component parts.

  1. Power System with outer command unit (СЭП, PS);
  2. Flat Cable Tester;
  3. Host Onboard Computer (БКУ,HOC);
  4. crimper for crimping the connectors to flat cable;
  5. screwdriver;
  6. cutting pliers;
  7. reaction wheel;
  8. sensors and transmitters;
  9. casing;
  10. battery charger (adapter);
  11. “solar panels”;
  12. flat cable;
  13. connectors;
  14. angle bars.

Educational Kit’s Assembling

Cable Network Assembling

Flat Cables are the key component of onboard cable network that serves for information exchange between subsystems ad host computer, also for powering of the subsystems.

All satellite subsystems are equipped with two redundant connectors to connect to onboard network. Consequently the apparatus connected to the onboard network not only available for information exchange but allows the chain-connection of subsequent subsystems via itself.

Information network built via bus architecture with RS-485 serial interfaces. To facilitate fitting, power lines and information bus are combined in one flat cable.

Subsustems’ connection is performed via DB-9F (“female”) connector from bundle side and via DB-9M (“male”) from apparatus side.

Since there’s possible a different composition of Educational Kit elements, the length of every flat cable shall be determined by the user (25-30 cm average).

To assemble the main bus, please take the nine-channel fat cable and DB-9F connectors:

Flat Cable Assembling

Via cutting pliers, cut the pieces of flat cable of required length.

To assemble the connector, make sure that every pin of the connector falls neatly to the one wire of the flat cable.

Then, put the assembled (but not yet crimped) flat cable into the crimper as shown on Figure. Before crimping, adjust the flat cable in connector if the cable has been accidentally displaced.

Please note: the connectors at the flat cable must be placed in identically oriented direction. If the connectors are oriented differently, there will be short-circuit failure.

Incorrect placement of the connectors on the flat cable.

It is necessary to observe that there’s no displacement of the flat cable as relative to pins in the connector as shown on Figure.

Once again, please note: the correct placement of connectors is critically important!

Correct assembling of the flat cable

Incorrect assembling of the flat cable

Attention! The cable for camera connection “male-male” must not be longer than 40 cm in length.

Flat Cables Check

There is a special tool for checking of the assembled flat cables, Flat Cable Tester. Before starting, the Flat Cable Tester must be connected to 220V power network via adapter.

To check the Flat Cable, it must be connected to two Tester’s connectors. Upon the color of the LED you may define the operability of the flat cable.

If the LED is yellow (“Circuit broken”), the circuit is broken. Most probably you have not crimped the flat cable properly.

If the LED is red (“Short-circuit failure”), it means either that you broke the isolation of two adjacent channels during crimping, or you incorrectly placed the connectors in relation to each other.

Cable Network Assembling

Cable network may be assembled either as serial connection of all network’s apparatuses via “point-to-point” flat cables, or as branching creation via flat cables equipped with more than two connectors.

Attention! Simultaneous connection to the one cable network of the apparatuses that are not designed for onboard use (“ground-based” RF-receiver and “ground-based” telemetry VHF receiver) and apparatuses of the onboard network is not permitted. It is critically important to exclude the possibility of simultaneous connection to one cable network of USB-RS485 ground segment connection cable and onboard power system (PS); otherwise the Educational Kit elements may be damaged.

Educational Kit’s Assembling

Prepare the elements required for installation of reaction wheel: Educational Kit’s base, Flywheel module, screws’ set. Connect the engine to satellite’s lower board (base). Attach the engine to base with the screws.

Take four side boards: satellite’s walls, PS module and HOC, also attaching screws’ set. Attach PS module to side board from inner side.

Attach plastic angle bars to the side board with screws. Put the side board into grooves of the base board and attach with screws and plastic angle bars.

Install the PS’ outer command unit from outside. Install HOC on other board and attach other boards to the base similar to first board. Connect the devises via flat cables.

Put the top cover of the case and attach it with plastic angle bars to the side boards. Fasten all screws in the angle bars. Attach with screws all required subsystems and connect them via flat cables to HOC and PS.

The assembling is finished!

Test program

Run the test program from previous lesson and check the kit’s functionality

en/lesson03.txt · Last modified: 2019/11/07 16:41 by golikov