Change Release Notes
This release is packed with performance boosts, smarter behavior, cleaner visuals, and a big step forward for education features. Under the hood, a lot has been reworked to make ARC faster, more stable, and more enjoyable to use across the board.
Core Improvements
EZ-B Communication Evolution
- Moved the EZ-B listener server out of the Connection robot skill and into a centralized ARC service
- This new shared service is now used by multiple robot skills, including the Camera device
- Improves scalability and reduces duplicated logic across skills
Faster, Safer Communication
- Improved Serial and Network EZ-B communication drivers
- Fixed a potential race condition
- Overall performance improvements for more reliable connections
HTTP Server Stability
- Fixed encoding issues in both
HttpServerandHttpServer Custom - Resolved a thread state bug that could cause instability
Performance & Rendering
Theme Renderer Upgrade
- Fixed a small GDI object memory leak
- Improved font clarity
- Better layer rendering for a cleaner UI experience
Video Pipeline Optimization
- Replaced legacy
memcpyusage with optimized memory copy buffers - Improved performance for video streaming and processing
Camera System Enhancements
Removed a potential race condition in the camera driver
Improved overall performance
New
UCCameraCanvas:- Maintains a local copy of bitmap memory
- Prevents UI from referencing freed memory
Added safety checks to ensure memory is valid before UI updates
Tracking Engine Boost
Significant optimizations across all camera tracking types:
- Object
- Color
- Custom Color
- Haar
- Custom YCbCr
- Face
- Glyph
- Motion
Expect faster and more responsive tracking across the board.
Scripting & Engine Improvements
Smarter Script Synchronization
- Optimized cancellation tokens in the scripting engine
- Blocking scripts now synchronize correctly with caller scripts
Waitcontrol commands now properly respect cancellation tokens
Cleaner API
- Removed
IsConnectedfrom Audio classes in JavaScript and Python - Use
EZB.IsConnected()instead
Speech Recognition Fixes
- Fixed an issue in Bing Speech Recognition where audio headers may not be fully written before transcription
- Resolved a rare threading issue under specific conditions
User Interface Improvements
Window Behavior Fix
Auto-position options window no longer restores window state when:
- Dragging the title bar
- Double-clicking the title bar
Prevents accidental resizing when using touchscreen servo controls
Numeric Selector Control
- Added option to enable/disable right-click manual entry
- Ideal for touchscreen devices to prevent accidental keyboard popups
IntelliSense Improvements
- JavaScript and Python editors now suppress IntelliSense popups when typing inside quotes
- Less intrusive and more context-aware suggestions
Blockly Enhancements
Visual Improvements
- Toolbox category colors now match their corresponding blocks
- Updated block colors for better distinction and readability
Organization
- Movement servo blocks moved into a dedicated Servo category
New Capability
Added
UI.waitForUserInput():- Available in JavaScript, Python, and Blockly
- Suspends script execution and prompts user for input
- Includes timeout support
- Found under the Text category in Blockly
Engine Updates
- Updated to Blockly v12.4.1
- Multiple fixes and stability improvements (ongoing testing continues)
Embedded Browser Enhancements
Now supports loading local files for:
- Sound effects
- Graphics used in Blockly
Camera & Audio Fixes
Removed UTF-8 and high ASCII characters from audio filenames in:
- SoundBoard PC
- SoundBoard EZ-B
Prevents compatibility issues across systems
Connection Experience
Connection robot skill now displays the EZ-B advertised name
Supports devices like:
- EZ-B v4
- ESP32
- IoTiny
Makes it easier to identify robots by friendly name instead of IP address
Education Features
Edu Activity Editor (First Release)
- Initial release of the Edu Activity Robot Skill
- Lays the foundation for creating structured educational content for ARC
Summary
This release focuses heavily on performance, stability, and usability:
- Faster camera and tracking systems
- More reliable communication and scripting
- Cleaner UI behavior and rendering
- Major groundwork for education features
Everything feels tighter, smoother, and more predictable-exactly what you want when building and controlling robots.
More updates are coming as the education system and Blockly enhancements continue to evolve.
ARC Downloads
ARC Free
Free
- Includes one free 3rd party plugin robot skill per project
- Trial cloud services
- Free with trial limitations
For schools, personal use & organizations. This edition is updated every 6-12 months.
ARC Pro
Only $8.99/mo
- 2 or more PCs simultaneously
- Includes unlimited skills
- Cloud backup
- And much more
Experience the latest features and bug fixes weekly. A Pro subscription is required to use this edition.
Runtime
Free
- Load and run any ARC project
- Operates in read-only mode
- Unlimited robot skills
- Early access fixes & features
Have you finished programming your robot? Use this to run existing ARC projects for free*.
- Minimum requirements are Windows 10 or higher with 2+gb ram and 500+MB free space.
- Recommended requirements are Windows 10 or higher with 8+gb ram and 1000+MB free space.
- Prices are in USD.
- ARC Free known-issues can be viewed by clicking here.
- Get more information about each ARC edition by clicking here.
- See what's new in the latest versions with Release notes.
Compare Editions
| Feature | ARC FREE |
ARC PRO |
|---|---|---|
| Get ARC for Free | View Plans | |
| Usage | Personal DIY Education |
Personal DIY Education Business |
| Early access to new features & fixes | Yes | |
| Simultaneous microcontroller connections* | 1 | 255 |
| Robot skills* | 20 | Unlimited |
| Skill Store plugins* | 1 | Unlimited |
| Cognitive services usage** | 10/day | 6,000/day |
| Auto-positions gait actions* | 40 | Unlimited |
| Speech recongition phrases* | 10 | Unlimited |
| Camera devices* | 1 | Unlimited |
| Vision resolution | max 320x240 | Unlimited |
| Interface builder* | 2 | Unlimited |
| Cloud project size | 128 MB | |
| Cloud project revision history | Yes | |
| Create Exosphere requests | 50/month | |
| Exosphere API access | Contact Us | |
| Volume license discounts | Contact Us | |
| Get ARC for Free | View Plans |
** 1,000 per cognitive type (vision recognition, speech recognition, face detection, sentiment, text recognition, emotion detection, azure text to speech)
Upgrade to ARC Pro
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