If you are of a certain age, you might remember when nearly every electronic device had a cord. You also might remember having been tripped, or tangled in those wires as well. In your home, the stakes were fairly low. That’s not usually the case in the field, where they can also pose real safety concerns.
As engineers working with fluid power cartridge valves, it’s important that you’re able to get close and observe machine operation during machine setup and calibration. Configuring without wires means the end of special cables, connectors and the need for a PC in the field.
It’s easy to imagine industrial applications that would benefit from Bluetooth-configurable valves. With a 30-ft range, Bluetooth reaches places that might otherwise require climbing with programming equipment, exposure to hazardous environments and increased time to connect and configure valves. With Bluetooth you can reconfigure installed amplifiers quickly and easily.
In 2007, Sun Hydraulics introduced its first embedded amplifier products. At the time, the best communication approach was an IR link for ease of connection and electrical noise immunity. But with the explosion of smartphone usage, Bluetooth communication made its way to the top of the short list for new connectivity options. The Sun design team saw this opportunity early on; the concern was how to make it a reality.
Perhaps the biggest challenge Sun faced during the design process was how to go wireless and add better software configurability without expanding the size of the embedded amplifier. It wasn’t until the introduction of Bluetooth Low Energy (BLE) and its effective miniaturization that Sun was able to include it in its embedded amplifiers.
For this project, Sun’s design team turned to its sister company, High Country Tek, which creates digital electronic controls for the fluid power industry. With High Country Tek’s experience designing and building totally encapsulated controllers, the Sun team was able to complete this complex product design while maintaining complete in-house control of the process.
To keep within the same form factor, they used a Bluetooth chipset and switched to a 16-bit processor coupled with a 10-bit A/D converter to enhance resolution and software configurability.
To account for environmental concerns, the Bluetooth embedded amplifiers were fully encapsulated for vibration, shock and environmental protection. They were also sealed to IP69K (with Deutsch DT04-6P connector) and IP65 ratings (with DIN 43650 A connector). They were CE certified, including the 30-V/m automotive standard per Directive 2009/19/EC. The amplifiers were tested on X, Y and Z axes over a frequency of 33.3 Hz at an overall level of 6.8 g for a total of four hours each. The end result was four Bluetooth Embedded Amplifiers meeting the same requirements as eight IR embedded amplifiers—all in the same form factor.
The next step was the interface for the new technology. This new version of the company’s embedded amplifier is configured by an iOS or Android app called AmpSet Blue.
The app made updates easier and eliminated the need for firmware updates. Customers would no longer have to download and install updates from a website. The latest versions would be available by opting to update the app from a mobile device. The Bluetooth embedded amplifier was designed with two indicator LEDs labeled “Power/Status” and “Active.” These LEDs allow the user to determine the status of the amplifier from a distance. When the app opens, the Bluetooth scan locates the amplifiers within range and supplies a list of available amplifiers. Once they select an amplifier, the Power/Status LED starts blinking, providing visual indication of the amplifier selected, then gives further feedback regarding the real-time operational status.
The design team also added the security options you find on most other mobile apps. Features include optional password protection to limit access of the amplifier’s configuration settings to authorized users only. Plus, the amplifier has a time-out feature that disconnects after a period of inactivity.
Filed Under: Sensors, Sensors & Gauges