Computer Vision and mBot extension

[Wang Yu]

Computer Vision Extension:

provides a simple computer vision plugin for color detection, face detection, and feature analysis (using online API).

http://learn.makeblock.com/en/user-makeblock-computer-vision-extension-for-app-inventor/

mBot Extension:

Use App Inventor to control Makeblock mBots.

http://learn.makeblock.com/en/use-mbot-with-app-inventor/

Playing with extensions has so much fun, though currently I cannot add any visible part to the extension I made.

That's why you need to use estimation instead of preview windows when you're doing computer vision tasks-_-

[Ghica]

That is very nice! I own an mBot, but so far I had no time or energy to figure out how to control it via Bluetooth. I will try this out in a few weeks. Thanks!
Cheers, Ghica.

[Alejandro Cañete]

Thank you very much!!

[Kumar]

Hi Yu,

I am trying to run this on my AI companion, and I get the below error. What would I be doing wrong?

Error from Companion: java.lang.RuntimeException: invalid syntax in eval form: :1:854: caught exception in inliner for # - java.lang.RuntimeException: no such class: com.google.appinventor.components.runtime.CamVision gnu.bytecode.ObjectType.getReflectClass(ObjectType.java:148) gnu.bytecode.ClassType.getModifiers(ClassType.java:103) gnu.bytecode.ClassType.isInterface(ClassType.java:471) gnu.expr.InlineCalls.checkType(InlineCalls.java:56) gnu.expr.InlineCalls.visit(InlineCalls.java:49) gnu.expr.InlineCalls.visitSetExpValue(InlineCalls.java:363) gnu.expr.InlineCalls.visitSetExpValue(InlineCalls.java:28) gnu.expr.ExpVisitor.visitSetExp(ExpVisitor.java:114) gnu.expr.InlineCalls.visitSetExp(InlineCalls.java:369) gnu.expr.InlineCalls.visitSetExp(InlineCalls.java:28) gnu.expr.SetExp.visit(SetExp.java:406) gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitLetExp(InlineCalls.java:317) gnu.expr.InlineCalls.visitLetExp(InlineCalls.java:28) gnu.expr.LetExp.visit(LetExp.java:207) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28) gnu.expr.LambdaExp.visitChildrenOnly(LambdaExp.java:1664) gnu.expr.LambdaExp.visitChildren(LambdaExp.java:1651) gnu.expr.InlineCalls.visitScopeExp(InlineCalls.java:279) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:349) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:28) gnu.expr.LambdaExp.visit(LambdaExp.java:1640) gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28) gnu.expr.ExpVisitor.visitAndUpdate(ExpVisitor.java:162) gnu.expr.ExpVisitor.visitExps(ExpVisitor.java:176) gnu.expr.ApplyExp.visitArgs(ApplyExp.java:416) gnu.kawa.reflect.CompileInvoke.validateApplyInvoke(CompileInvoke.java:23) java.lang.reflect.Method.invokeNative(Native Method) java.lang.reflect.Method.invoke(Method.java:525) gnu.expr.InlineCalls.maybeInline(InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.kawa.functions.CompilationHelpers.validateApplyToArgs(CompilationHelpers.java:66) java.lang.reflect.Method.invokeNative(Native Method) java.lang.reflect.Method.invoke(Method.java:525) gnu.expr.InlineCalls.maybeInline(InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:119) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:28) gnu.expr.ApplyExp.visit(ApplyExp.java:411) gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.QuoteExp.validateApply(QuoteExp.java:162) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.kawa.functions.CompilationHelpers.validateApplyToArgs(CompilationHelpers.java:66) java.lang.reflect.Method.invokeNative(Native Method) java.lang.reflect.Method.invoke(Method.java:525) gnu.expr.InlineCalls.maybeInline(InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:119) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:28) gnu.expr.ApplyExp.visit(ApplyExp.java:411) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28) gnu.expr.LambdaExp.visitChildrenOnly(LambdaExp.java:1664) gnu.expr.LambdaExp.visitChildren(LambdaExp.java:1651) gnu.expr.InlineCalls.visitScopeExp(InlineCalls.java:279) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:349) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:28) gnu.expr.ExpVisitor.visitModuleExp(ExpVisitor.java:103) gnu.expr.ModuleExp.visit(ModuleExp.java:482) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.inlineCalls(InlineCalls.java:33) gnu.expr.Compilation.walkModule(Compilation.java:994) gnu.expr.Compilation.process(Compilation.java:1965) gnu.expr.ModuleInfo.loadByStages(ModuleInfo.java:330) gnu.expr.ModuleExp.evalModule1(ModuleExp.java:238) gnu.expr.ModuleExp.evalModule(ModuleExp.java:198) gnu.expr.Language.eval(Language.java:943) gnu.expr.Language.eval(Language.java:883) gnu.expr.Language.eval(Language.java:865) com.google.appinventor.components.runtime.util.AppInvHTTPD.serve(AppInvHTTPD.java:191) com.google.appinventor.components.runtime.util.NanoHTTPD$HTTPSession.run(NanoHTTPD.java:476) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573) java.lang.Thread.run(Thread.java:838)

[Taifun]

after importing an extension, you have to restart the companion app

Taifun

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Trying to push the limits of App Inventor! Snippets, Tutorials and Extensions from Pura Vida Apps by Taifun.