A psuedo Candarm/drone for stock?

[Jestersage]

Obviously, there's no Candaarm in stock game. So if I want to make a drone with the KLAW, what do I need to make it works? Do I need to watch for thrust, the weight, the TWR?

[Reactordrone]

If it just has to move things around a space station at close range you can have a fairly simple monoprop powered vehicle, especially of you've placed thruster quads on the modules (regardless of whether the module has any monopropellant itself). It can be useful to have the RCS system set up so that it only does translation manoeuvres and keep the rotation to reaction wheels. that tends to save the SAS blowing through all of your fuel when it's pointing at the target. You may also want to mark the top of the vehicle with an antenna or something to make it easy to align the vehicle to match the IJKL keys.

[fourfa]

If you want a stock Canadarm / Krakenarm for grabbing and manipulating things very near a station - check this out:

https://kerbalx.com/EJ_SA/KrakenArm-31

100% stock articulated arm, using cages around Stayputniks as ball and socket joints, and reaction wheels to move separate sections of the arm.

Otherwise, just slap a battery, reaction wheel, and RCS on a probe core and go to work.  I like Klaw on one side and docking port on the other, and a light or two.  TWR and size hardly matter - even a single ring of RCS quads is enough power to move some pretty large components, and with enough reaction wheel power it hardly matters that your RCS thrust will usually be off-center.  Definitely de-activate RCS on the rotation axes as noted above (I have a custom cfg for that by default)

[Vive_moi]

Hello,

There is my station automated tug (under the station). Do not forget the antenna. ;-)

1 docking port junior, 4 4-ways RCS ports (tuned to be on the COM and all rotations disabled), 4 Universal storage monoprop tank, 1 small reaction wheel, 4x ox-stat panel, 1 service bay with 4 z-100 battery, 1 drone core and 1 RemoteTech DP-10.

The COM does not move so much when the tank are emptying. The only small problem it has is the reaction wheel is way too powerfull when the tug is alone and it start jitter. In this case, add an action group to or manually  switch off/on the reaction wheel.

If you play stock, plug a docking port for the tug on each thing you need to move. If you play modded (as I do), you can use KIS to plug a temporary docking port to move the thing and remove it after.

See you,

Vive_moi

Edited August 24, 2016 by Vive_moi

[mhoram]

It is a bit difficult to give a suggestion for TWR, because it depends on several factors like the mass of the drone and the mass of the object you want to transport.
The larger the mass of the object you want to transport, the lower the resulting TWR will get.

Regarding fuel you should have enough for performing your operations and you can refuel the drone after an operation, so keep a supply of fuel on your main station. Also keep in mind that grabbling another object means that you add mass to your ship which reduces the Delta-V you can expend.

Another consideration you should take into account is torque. If your drone has too little torque, it will get tedious for you to transport and aim other objects. (In some cases I attached more than one Tuggy's (see below) to the object I was transporting in order to get a better handling)

Lamps (together with batteries and solar panels) are (at least for me) essential: sooner or later it can happen that during the docking maneuver you move into the planets shadow where docking without light is quite problematic.

Personally I find that the claw is unpleasant to handle, since it is difficult to attach it near the center of mass of the intended target, which makes precision maneuvering quite problematic, so I keep mostly to docking ports.

Also there are two approaches for the craft, which have different implications: puller or pusher designs.
- Puller designs with the claw are more stable than pusher designs, but can make docking the transported object difficult.
- Pusher designs are easier do create, since you don't need to take care that the exhaust of the engines reaches the object you transport.

All in all I would recommend, that you try out a design and change the details that don't work out for you.

 

The solution I use for my space stations is the transport tug "Tuggy", a small RCS-fueled craft with large docking ports. It took about 5 design iterations of more or less viable crafts until I came to this design that fulfills most of my needs.

And the cool part is, that it is stackable, because it has on both ends large docking ports.

Edited August 24, 2016 by mhoram