# URCaps SDK **URL:** https://forum.universal-robots.com/c/urcap-development/sdk/6.md [Latest](https://forum.universal-robots.com/latest.md) · [Categories](https://forum.universal-robots.com/categories.md) · [Tags](https://forum.universal-robots.com/tags.md) --- ## [About the URCaps SDK category](https://forum.universal-robots.com/t/about-the-urcaps-sdk-category/22)
**Author:** [@jbm](https://forum.universal-robots.com/u/jbm)\ **Replies:** 1\ **Last updated:** [May 16, 2017, 5:30am UTC](https://forum.universal-robots.com/t/about-the-urcaps-sdk-category/22 "2017-05-16T05:30:19Z")
Questions related to the SDK provided for development of URCaps. --- ## [Archetype com.ur.urcap:archetype:1.18.0](https://forum.universal-robots.com/t/archetype-com-ur-urcap1-18-0/42702)
**Author:** [@jorge.turiel](https://forum.universal-robots.com/u/jorge.turiel)\ **Replies:** 2\ **Last updated:** [August 6, 2026, 8:10am UTC](https://forum.universal-robots.com/t/archetype-com-ur-urcap1-18-0/42702 "2026-08-06T08:10:28Z")
Hello, I installed docker in windows, following this Dev Containers Setup Tutorial — PolyScope Tutorials documentation I downloaded the sdk from here GitHub - UniversalRobots/PolyScopeX\_URCap\_SDK · GitHub I open the fo… --- ## [URCAP ERROR HANDLING: The URCap needs a 3rd party dependency which is not available (CB3 Series)](https://forum.universal-robots.com/t/urcap-error-handling-the-urcap-needs-a-3rd-party-dependency-which-is-not-available-cb3-series/42409)
**Author:** [@brunosoliveras](https://forum.universal-robots.com/u/brunosoliveras)\ **Replies:** 1\ **Last updated:** [March 12, 2026, 8:30am UTC](https://forum.universal-robots.com/t/urcap-error-handling-the-urcap-needs-a-3rd-party-dependency-which-is-not-available-cb3-series/42409 "2026-03-12T08:30:55Z")
Hi, I am currently using the SDK 1.17.0 to develop a URCap. I figured I start by studying the swing examples that came inside the SDK. At first, I was using a virtual machine for E-Series 5.22 and executed the command “… --- ## [PolyScope X SDK simulator won't run with Docker 29](https://forum.universal-robots.com/t/polyscope-x-sdk-simulator-wont-run-with-docker-29/42262)
**Author:** [@timb](https://forum.universal-robots.com/u/timb)\ **Replies:** 0\ **Last updated:** [February 16, 2026, 9:22pm UTC](https://forum.universal-robots.com/t/polyscope-x-sdk-simulator-wont-run-with-docker-29/42262 "2026-02-16T21:22:29Z")
When trying to run the simulator in the PolyScope X SDK with Docker 29 this error is displayed. “Error response from daemon: client version 1.43 is too old. Minimum supported API version is 1.44, please upgrade your cl… --- ## [Sign ambiguity when receiving poses](https://forum.universal-robots.com/t/sign-ambiguity-when-receiving-poses/42253)
**Author:** [@mat.elwarth](https://forum.universal-robots.com/u/mat.elwarth)\ **Replies:** 0\ **Last updated:** [February 16, 2026, 3:50am UTC](https://forum.universal-robots.com/t/sign-ambiguity-when-receiving-poses/42253 "2026-02-16T03:50:05Z")
I’m creating a palletizing URCap, but am getting odd results when training poses. Say I want to define a grid by teaching the four corners and an approach. I’m using the standard API callbacks, but the rotation values o… --- ## [How to download URCap archive version?](https://forum.universal-robots.com/t/how-to-download-urcap-archive-version/39808)
**Author:** [@jaehong.yoo](https://forum.universal-robots.com/u/jaehong.yoo)\ **Replies:** 3\ **Last updated:** [February 12, 2026, 6:28am UTC](https://forum.universal-robots.com/t/how-to-download-urcap-archive-version/39808 "2026-02-12T06:28:41Z")
Hello, I’m new to Universal Robots and have just started working with the UR5 (not the UR5e). I’m using a CB3 controller running Polyscope 3.15, which I understand is the latest available for CB3. According to the UR we… --- ## [PolyScope X SDK Without The VSCode Lockin](https://forum.universal-robots.com/t/polyscope-x-sdk-without-the-vscode-lockin/42047)
**Author:** [@cg1](https://forum.universal-robots.com/u/cg1)\ **Replies:** 0\ **Last updated:** [January 18, 2026, 4:51pm UTC](https://forum.universal-robots.com/t/polyscope-x-sdk-without-the-vscode-lockin/42047 "2026-01-18T16:51:52Z")
Hi everyone. When using the PolyScope X SDK, because of the use of a “devcontainer.json” file as well as the way permission and ownership of files and folders have been set up. Using anything but VSCode for URCapX devel… --- ## [CustomAPI in polyscopex](https://forum.universal-robots.com/t/customapi-in-polyscopex/41926)
**Author:** [@funing.hu](https://forum.universal-robots.com/u/funing.hu)\ **Replies:** 0\ **Last updated:** [December 5, 2025, 10:13am UTC](https://forum.universal-robots.com/t/customapi-in-polyscopex/41926 "2025-12-05T10:13:04Z")
Hello, i’m pulling some efforts to work on CustomAPI in PolyScope X context, inheriting a super useful URCap Sample: URCap CustomAPI in PolyScope5. Feel free to check it out and leave your any feedback/thinking to guid… --- ## [Polyscope X Error installing urcapx on physical robot and simulator](https://forum.universal-robots.com/t/polyscope-x-error-installing-urcapx-on-physical-robot-and-simulator/41759)
**Author:** [@hpous](https://forum.universal-robots.com/u/hpous)\ **Replies:** 1\ **Last updated:** [November 20, 2025, 11:58am UTC](https://forum.universal-robots.com/t/polyscope-x-error-installing-urcapx-on-physical-robot-and-simulator/41759 "2025-11-20T11:58:34Z")
Hello everyone, I am developing an URCAP for the new Polyscope X. For some time now, I have been implementing the backend in Python and the frontend in Angular. I was able to simulate it correctly during development, bu… --- ## [How I Create Child Node with position](https://forum.universal-robots.com/t/how-i-create-child-node-with-position/41371)
**Author:** [@vytor645](https://forum.universal-robots.com/u/vytor645)\ **Replies:** 1\ **Last updated:** [October 2, 2025, 6:11pm UTC](https://forum.universal-robots.com/t/how-i-create-child-node-with-position/41371 "2025-10-02T18:11:38Z")
Hi guys, Good Morning for all. I’m having trouble with my URCAP; I can’t create a subnode in the program tree in a way that assigns a fixed or specific position to that subnode. Can anyone help me with this? --- ## [ScriptBuilder bad indentation on elif and else](https://forum.universal-robots.com/t/scriptbuilder-bad-indentation-on-elif-and-else/40811)
**Author:** [@mnj](https://forum.universal-robots.com/u/mnj)\ **Replies:** 4\ **Last updated:** [August 15, 2025, 12:25pm UTC](https://forum.universal-robots.com/t/scriptbuilder-bad-indentation-on-elif-and-else/40811 "2025-08-15T12:25:59Z")
Hi all, Look at what indentation this code snippet from typescript gives. Typescript: // only for testing builder.ifCondition("myVar") builder.localVariable("resultVar", "1") builder.elseIfCondition("yourVar") … --- ## [SDK Docker ursim Error directory](https://forum.universal-robots.com/t/sdk-docker-ursim-error-directory/40812)
**Author:** [@timo.schillinger](https://forum.universal-robots.com/u/timo.schillinger)\ **Replies:** 0\ **Last updated:** [August 12, 2025, 1:20pm UTC](https://forum.universal-robots.com/t/sdk-docker-ursim-error-directory/40812 "2025-08-12T13:20:25Z")
Hi, I can’t save or load any programs in the SDK ursim. I have downloaded the latest SDK from GitHub. Doese anyone have an idea to solve this problem? --- ## [Open move tab with Feature 'Tool' (instead of 'View')](https://forum.universal-robots.com/t/open-move-tab-with-feature-tool-instead-of-view/40759)
**Author:** [@felix.hartenbach](https://forum.universal-robots.com/u/felix.hartenbach)\ **Replies:** 0\ **Last updated:** [August 6, 2025, 12:12pm UTC](https://forum.universal-robots.com/t/open-move-tab-with-feature-tool-instead-of-view/40759 "2025-08-06T12:12:14Z")
Is it possible to open the move tab/page from an UrCap and select the ‘Tool’ Feature by default? Currently it defaults to the Feature ‘View’. VS Motivation: Our user shall configure a new TCP, the new TCP requi… --- ## [Is It Safe to Update UR Software? how?](https://forum.universal-robots.com/t/is-it-safe-to-update-ur-software-how/40698)
**Author:** [@farzaneh.gerami](https://forum.universal-robots.com/u/farzaneh.gerami)\ **Replies:** 3\ **Last updated:** [August 4, 2025, 5:20am UTC](https://forum.universal-robots.com/t/is-it-safe-to-update-ur-software-how/40698 "2025-08-04T05:20:52Z")
Hi, I have a question. How can I update the Universal Robots Polyscope software from version 5.11 to 5.15 or later? I’m near the end of my project and considering the update because I need to use matrices or lists in U… --- ## [Equipamento liga a tela por 5 segundos apenas](https://forum.universal-robots.com/t/equipamento-liga-a-tela-por-5-segundos-apenas/40565)
**Author:** [@andre2896a](https://forum.universal-robots.com/u/andre2896a)\ **Replies:** 0\ **Last updated:** [July 16, 2025, 12:04am UTC](https://forum.universal-robots.com/t/equipamento-liga-a-tela-por-5-segundos-apenas/40565 "2025-07-16T00:04:38Z")
O robô após energizado em 220vac e colocado fonte 24vdc externa conforme manual, a IHM liga por apenas 5 segundos e desliga após isso. Foi feito várias tentativas e não funcionou --- ## [Remote TCP & Toolpath URCap Controller Start Failed](https://forum.universal-robots.com/t/remote-tcp-toolpath-urcap-controller-start-failed/8252)
**Author:** [@anon27918815](https://forum.universal-robots.com/u/anon27918815)\ **Replies:** 9\ **Last updated:** [March 27, 2025, 5:57pm UTC](https://forum.universal-robots.com/t/remote-tcp-toolpath-urcap-controller-start-failed/8252 "2025-03-27T17:57:17Z")
Hi everyone, I am trying to test one of the g-code files using the Remote TCP & Toolpath URCap. I am doing it on URSim for testing purpose. Unfortunately, for some reason, when I start the controller under Installation\>U… --- ## [Get Waypoint name](https://forum.universal-robots.com/t/get-waypoint-name/38177)
**Author:** [@claudia](https://forum.universal-robots.com/u/claudia)\ **Replies:** 1\ **Last updated:** [February 12, 2025, 2:23pm UTC](https://forum.universal-robots.com/t/get-waypoint-name/38177 "2025-02-12T14:23:06Z")
I’m working on a URCap where I need to collect the names of all waypoint that are children of my URcap node. I can successfully traverse the waypoint children using the code below and retrieve their poses (for fixed\_posi… --- ## [RobPod HMI / URCaps](https://forum.universal-robots.com/t/robpod-hmi-urcaps/37203)
**Author:** [@leonardo.valente](https://forum.universal-robots.com/u/leonardo.valente)\ **Replies:** 0\ **Last updated:** [November 29, 2024, 10:56am UTC](https://forum.universal-robots.com/t/robpod-hmi-urcaps/37203 "2024-11-29T10:56:31Z")
I’m trying to create my first HMI URCaps with RobPod software. Is there a way i can link each button to show different information on the input buttons, and if the operator type something different on it save it as new … --- ## [UR Cap OnRobot 2FG14 throws error - "twofg command did not apply the force at the end"](https://forum.universal-robots.com/t/ur-cap-onrobot-2fg14-throws-error-twofg-command-did-not-apply-the-force-at-the-end/36532)
**Author:** [@rgarewal](https://forum.universal-robots.com/u/rgarewal)\ **Replies:** 5\ **Last updated:** [October 16, 2024, 6:00pm UTC](https://forum.universal-robots.com/t/ur-cap-onrobot-2fg14-throws-error-twofg-command-did-not-apply-the-force-at-the-end/36532 "2024-10-16T18:00:44Z")
Every time I try to grip a cube, the gripper fingers move and grip the object. However, right after the command is executed the error is shown and the program is halted. How do I resolve this issue? --- ## [Using Features while in a Program Node Contribution class](https://forum.universal-robots.com/t/using-features-while-in-a-program-node-contribution-class/34674)
**Author:** [@tsanzo](https://forum.universal-robots.com/u/tsanzo)\ **Replies:** 1\ **Last updated:** [June 10, 2024, 6:18pm UTC](https://forum.universal-robots.com/t/using-features-while-in-a-program-node-contribution-class/34674 "2024-06-10T18:18:29Z")
I am trying to get a list of Features in a Program Node Contribution class. But when I call the FeatureModel getGeomFeatures() I don’t get any return values. More context I am using the ProgramAPIProvider .getProgramAPI… --- ## [MyFirstURCap failed to start ursim](https://forum.universal-robots.com/t/myfirsturcap-failed-to-start-ursim/34303)
**Author:** [@coco](https://forum.universal-robots.com/u/coco)\ **Replies:** 0\ **Last updated:** [May 19, 2024, 7:17pm UTC](https://forum.universal-robots.com/t/myfirsturcap-failed-to-start-ursim/34303 "2024-05-19T19:17:15Z")
After modifying the code by tutorial, I executed “./start-ursim.sh”, error happended. LightUp registering! 12:03:24.818 ERROR - Error processing URCaps {thread: Thread-3 , loggerClass: com.ur.urcap.osgi.BundleServicesBi… --- ## [Installation DataModel don't restore its values](https://forum.universal-robots.com/t/installation-datamodel-dont-restore-its-values/915)
**Author:** [@anon58863070](https://forum.universal-robots.com/u/anon58863070)\ **Replies:** 17\ **Last updated:** [April 24, 2024, 7:40am UTC](https://forum.universal-robots.com/t/installation-datamodel-dont-restore-its-values/915 "2024-04-24T07:40:46Z")
Hello. I'm trying to save some parameters in the DataModel on an installation urcap, and I noticed that (at least on the sim), when I shutdown it and restart it, I can't get my values back. Of course, I know that I hav… --- ## [UR3e with a realsense depth camera D435i](https://forum.universal-robots.com/t/ur3e-with-a-realsense-depth-camera-d435i/27114)
**Author:** [@anon52454696](https://forum.universal-robots.com/u/anon52454696)\ **Replies:** 3\ **Last updated:** [September 21, 2023, 9:16pm UTC](https://forum.universal-robots.com/t/ur3e-with-a-realsense-depth-camera-d435i/27114 "2023-09-21T21:16:40Z")
Hello, I’m new to this forum. I have recently been working with the universal robot and it has been a great experience so far. I now received the intel realsense depth camera D435i. My goal at my university is to integr… --- ## [Keyboard display format createDoubleKeypadInput()](https://forum.universal-robots.com/t/keyboard-display-format-createdoublekeypadinput/30279)
**Author:** [@tsuji.yoshiki](https://forum.universal-robots.com/u/tsuji.yoshiki)\ **Replies:** 0\ **Last updated:** [September 5, 2023, 1:09am UTC](https://forum.universal-robots.com/t/keyboard-display-format-createdoublekeypadinput/30279 "2023-09-05T01:09:02Z")
Hello. I am in trouble. I am using createDoubleKeypadInput(). When I set the initial value to -0.700 with setInitialValue(), what is displayed on the keyboard is -.7. Is there any way to change the format displaye… --- ## [Proper way to use an URCap as a dependency](https://forum.universal-robots.com/t/proper-way-to-use-an-urcap-as-a-dependency/24269)
**Author:** [@anon34306213](https://forum.universal-robots.com/u/anon34306213)\ **Replies:** 3\ **Last updated:** [August 24, 2023, 10:40am UTC](https://forum.universal-robots.com/t/proper-way-to-use-an-urcap-as-a-dependency/24269 "2023-08-24T10:40:51Z")
Hello, I am facing an interesting issue that I think will help many future progarmmers if we are able to find a solutio together. Imagine you created an URCap that does something very simple, let’s say turning on and o… --- ## [Set I/O Action in Program via SDK](https://forum.universal-robots.com/t/set-i-o-action-in-program-via-sdk/29355)
**Author:** [@francis](https://forum.universal-robots.com/u/francis)\ **Replies:** 4\ **Last updated:** [July 6, 2023, 12:57am UTC](https://forum.universal-robots.com/t/set-i-o-action-in-program-via-sdk/29355 "2023-07-06T00:57:21Z")
In the Installation Settings, under I/O Setup, the user can set an I/O’s actions. For example, an input can be assigned to Program start or Freedrive. An output can be assigned to Low when program is stopped. Does any… --- ## [Add child to MoveNode](https://forum.universal-robots.com/t/add-child-to-movenode/19335)
**Author:** [@sl11](https://forum.universal-robots.com/u/sl11)\ **Replies:** 1\ **Last updated:** [May 11, 2023, 10:26am UTC](https://forum.universal-robots.com/t/add-child-to-movenode/19335 "2023-05-11T10:26:02Z")
Hey Context: The URcap that I have made uses none of the Universal Robot own nodes in creating a path. This introduces a problem that the program does not start with the “Move Robot into Position” page which is require… --- ## [Active Terminal in Polyscope 6](https://forum.universal-robots.com/t/active-terminal-in-polyscope-6/28141)
**Author:** [@eric.feldmann](https://forum.universal-robots.com/u/eric.feldmann)\ **Replies:** 2\ **Last updated:** [April 27, 2023, 12:53pm UTC](https://forum.universal-robots.com/t/active-terminal-in-polyscope-6/28141 "2023-04-27T12:53:13Z")
Does anyone know how to show the active terminal when deploying a CAP to the Polyscope 6 Simulator? Before, when you mvn installed the CAP, it put you directly into the terminal so you could see things like your System.o… --- ## [URcaps loading order](https://forum.universal-robots.com/t/urcaps-loading-order/27688)
**Author:** [@petar.milosevic](https://forum.universal-robots.com/u/petar.milosevic)\ **Replies:** 0\ **Last updated:** [March 30, 2023, 3:23pm UTC](https://forum.universal-robots.com/t/urcaps-loading-order/27688 "2023-03-30T15:23:26Z")
I have three plugins (URCaps). I do not know the order of their initialization. All of them have their own daemon implemented in python. “Communication layer” is XML-RPC. In python, during initialization, connection with… --- ## [URCap SDK (But I Dockerized it)](https://forum.universal-robots.com/t/urcap-sdk-but-i-dockerized-it/25742)
**Author:** [@phye](https://forum.universal-robots.com/u/phye)\ **Replies:** 16\ **Last updated:** [March 21, 2023, 8:37am UTC](https://forum.universal-robots.com/t/urcap-sdk-but-i-dockerized-it/25742 "2023-03-21T08:37:36Z")
Hey URCap Dev community, I put the SDK on Docker, and linked it to the URSim that’s on Docker so that it’s easier to develop and deploy URCaps. Please let me know if you have feedback and such. Hopefully, this is easier… [Next page](https://forum.universal-robots.com/c/urcap-development/sdk/6.md?page=1)