From industrial automated machines to humanoids that mimic human behavior, robots require some of the most advanced control systems and complex mechanical structures available today. Robots are often deployed in dynamic environments that make development more challenging. Even the most advanced software simulations cannot account for all of the variables in a real-world environment. To know how a robot will respond to different situations prior to production, a functional prototype is vital.
By combining NI LabVIEW graphical system software with an off-the-shelf platform, you can develop software and have a fully functional prototype in one month or less. You should base your development platform selection on a number of factors, including price, flexibility, I/O count, processor speed, ruggedness and on-board sensors. Some of the most common platforms used for prototyping span from the LEGO® MINDSTORMS® NXT, all the way to embedded NI CompactRIO and NI Single-Board RIO systems. Table 1 provides a comparison of available platforms.
|Robot Base||iRobot Create Plus Command Module||LEGO MINDSTORMS NXT Base Set||NI Single-Board RIO Evaluation Kit||MobileRobots Inc Pioneer 3-DX|
|Starting Price||$229.99 USD||$279.95 USD||$999.00 USD||More than $1,000 USD|
|Processor Speed||18 MHz||48 MHz||400 MHz||50 MHz|
|RS232 Interface||1 port||None||1 port||3 ports|
|Custom I/O||25 DIO, AI, and AO||4 input ports and 3 output ports||110 DIO, 32 AI, and 4 AO||8-bit external I/O bus with up to 16 devices + PC104|
|Nonvolatile Storage||144 KB||256 KB||256 Mb||1 Mb|
|Terrain Capabilities||Indoor, flat floors, 2.27 kg payload||
Indoor, flat floors,3 kg payload
|Motors and wheels of your choice||Indoor, more than 2.5 cm sills, up wheelchair-compliant ramps with 14-23kg payload|
|Ships with Sensors||Yes||Yes||No||Yes|
Table 1. There is a prototyping platform available for almost every robot application and price point.
1. Prototyping with LEGO MINDSTORMS NXT
LEGO MINDSTORMS NXT includes an intelligent, computer-controlled LEGO brick that is perfect for prototyping on a tight budget. It consists of a 32-bit ARM microcontroller that you can use with a variety of sensors and motors. By using the LabVIEW Toolkit for LEGO MINDSTORMS NXT, you can create programs that can be downloaded directly to the NXT brick. With 10-bit analog-to-digital converters (ADCs) as inputs, the NXT brick can behave as a data acquisition unit that can control up to three motors and revolution counters.
Ngee Ann Polytechnic Institution’s School of Engineering developed an autonomous vision-guided robot to collect tennis balls. By using a camera to acquire images and NI vision software to perform object tracking, the machine performs this task with high precision and speed. In reality, you need a larger ball collection system to perform on full-scale tennis courts, but Ngee Ann Polytechnic reduced costs by testing their theories on their NXT prototype.
Figure 1. Ngee Ann Polytechnic Institution’s School of Engineering developed an autonomous vision-guided robot with LabVIEW to collect tennis balls.
2. Prototyping with the iRobot Create
If you are looking for quick development time and a low price, the iRobot Create comes fully assembled for less than $300 USD. The iRobot Create is a dependable, versatile robot base that you can use for robotics hobby and research applications. It has 32 built-in sensors, two powered wheels, a castor, 10 preprogrammed behaviors, an expandable input/output port for custom sensors and actuators, a cargo bay with mounting points, and a tailgate for ballast.
Figure 2. Boston Engineering built a dancing, singing iRobot Create using LabVIEW.
Boston Engineering recently took the iRobot Create to new levels. By adding a FlexStack module that could be programmed with LabVIEW, they programmed their robot to square dance and sing songs. The robot performs a different dance based on the RFID tag that it reads. Because of the productivity of graphical programming, Boston Engineering developed the application in such a short period of time that they actually spent more time developing the plastic housing for the FlexStack than they did programming the robot. Because they used LabVIEW, the iRobot Create was dancing and singing in less than one day.
3. Prototyping with NI Single-Board RIO and NI CompactRIO
There are many preassembled, out-of-the-box robot platforms available that you can use to develop your prototype in just a couple of weeks. However, if your robot prototype requires a flexible platform with deterministic real-time execution, custom I/O timing, and advanced control, such as a fully autonomous vehicle like Virginia Tech’s Odin or the Vecna BEAR, consider the CompactRIO and NI Single-Board RIO embedded platforms. These platforms are designed for high performance and reliability. CompactRIO is a more rugged platform that shares the same architecture and components. With CompactRIO or NI Single-Board RIO as the base of your robot, you have the ability to customize the construction, mobility, sensing, and I/O.
With LabVIEW graphical programming tools and a RIO embedded platform, you can quickly develop a fully functional autonomous robot. KC BioMediX Inc, a start-up medical device company based in Shawnee, Kansas, developed a product called NTrainer System to help premature babies learn to oral feed, which may increase their chances of survival. With LabVIEW and CompactRIO, KC BioMediX, Inc. was able to reduce its development costs by $250,000 USD. In addition, they were able to reduce their development time from four months to four weeks, and avoid the necessity of developing custom control software and drivers.
Figure 3. With LabVIEW and CompactRIO, KC BioMediX Inc was able to reduce its development costs by $250,000 USD.
4. Prototyping with MobileRobots Inc.
Figure 4. SpeciMinder, a robot developed by CCS Robotics using a MobileRobots PatrolBot Base, is being brought to hospitals by CCS Robotics.
If you need of an out-of-the box solution with flexibility, MobileRobots Inc. offers a platform for almost every purpose at every price. If you are looking for a robot with “robotiquette” that can interact with humans, the PeopleBot and GuiaBot know how to behave socially. If you are looking for an all-terrain platform, the P3AT is a team performer for outdoor or rough-terrain projects. The P3DX is the most popular classroom robot, while PowerBot is available for heavy-duty work such as carrying industrial arms.
The MobileRobots Inc. PatrolBot base is already being used in the industry to deliver specimens to various laboratories within hospitals. Carrying samples in the SpeciMinder top, developed by CCS Robotics, PatrolBot travels from station to station without needing any human intervention. It announces its presence, waits to be loaded, and then heads to its next station. If something is blocking its path, the robot finds a way around it, or takes a different hallway. Several SpeciMinders, installed over a year ago, have traveled more than 10,000 km.
Functional prototypes can reduce development time and costs. From low-cost solutions requiring a minimal amount of I/O such as the tennis ball picker based on LEGO MINDSTORMS NXT, to high channel-count, deterministic solutions such as the NTrainer System based on CompactRIO, there is a robot platform available for almost every application. By programming your robot with LabVIEW, you can easily prototype your robot in one month or less.
Check out ni.com/robotics for videos, case studies, product information, and other robotics-related content.
Meghan Meckstroth is an NI applications engineer who focuses on robotics technology. She holds a bachelor's degree in mechanical engineering from the University of Tennessee.
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