Facilities and Equipment at DCSL

Last updated: July 13, 2021


In DCSL, we maintain a leading-edge testbed with embedded devices with GPUs on them. The testbed is heterogeneous and has four different classes of nodes (Jetson Nano, Jetson TX2, Jetson Xavier NX, and Jetson AGX Xavier. They are distributed in three locations across Purdue campus, thus affording another degree of heterogeneity. The testbed is set up for remote access and is routinely used by our external collaborators. The testbed devices in each subnet are connected to an external monitor and keyboard allowing for facilities like macroprogramming and monitoring of the loads on the devices.

NVIDIA Jetson embedded devices

Embedded AI testbed site


In DCSL, we have two server clusters to perform computation-intensive tasks. For CPU intensive tasks, like high-performance computing, we have multi-core machines with up to 48 CPUs. For GPU intensive tasks, like training machine learning models, we have a small cluster rwith GPU capability, each equipped with high-end NVIDIA GPU cards (P100 GPU cards). Apart from the in-house machines, our researchers regularly run their tasks on public cloud services, like Amazon AWS, Google Compute, and Microsoft Azure. We have an annual research award from Amazon which allows all our researchers to use AWS compute credits.

Amazon.com: NVIDIA Tesla P100 16GB PCIe 3.0 Passive GPU ...


Researchers at DCSL have access to many lightweight and energy saving IoT devices that are used in evaluating algorithms developed. The latest version of Raspberry Pi 4 Model B is available in the lab.  Researchers at DCSL have used Raspberry Pi as an edge device which collects data from sensors through the IoT network and analyze the data on the edge that can minimize the latency of data processing.

Figure 1. Hardware Architecture of Raspberry Pi 4 Model B [1]

In addition, DCSL also offers a testbed of ARM development boards which allows us to build, test and evaluate various protocols. Currently, the testbed is being used to evaluate the energy consumption in consensus protocols.


STM32F401RE with BLE extension board

Figure 2. STM32F401RE with BLE Extension Board, used for our distributed embedded security testbed


Table 1. IoT Devices Used in The Testbeds at DCSL



CPU / Memory

Additional Features

Raspberry Pi


Pi 4

64-bit quad-core processor, 4GB of RAM

Dual-display support at resolutions up to 4K via a pair of micro-HDMI ports, Dual-band 2.4/5.0 GHz Wireless LAN, Bluetooth 5.0, Gigabit Ethernet, USB 3.0, and PoE capability



ARM®32-bit Cortex®-M4 CPU with FPU, 512 KB Flash, 96 KB SRAM

External BLE and WiFi Boards are available, Arduino Uno Revision 3 connectivity



32-bit ARM®Cortex®-M4 with FPU core, 1-Mbyte Flash memory, 192-Kbyte RAM

BLE extension available, LIS302DL or LIS3DSH ST MEMS 3-axis accelerometer




Sampling digital and analog signals from embedded boards, compatible with current sensor, TI-INA169 that can be used to measure energy.



Figure 3. Raspberry Pi 4 Model B [2]


[1] https://www.raspberrypi.org/products/raspberry-pi-4-model-b/specifications/



Researchers at DCSL have access to edge devices such as Jetson TX2 to implement Deep Neural Networks (DNN). Jetson TX2 is the fastest and most power-efficient embedded AI computing device. This 7.5-watt supercomputer on a module brings true AI computing at the edge. It’s built around an NVIDIA Pascal™-family GPU and loaded with 8GB of memory and 59.7GB/s of memory bandwidth. It features a variety of standard hardware interfaces that make it easy to integrate it into a wide range of products and form factors. [1]
The specification of TX2 is as following:

Ø  2+4 CPUs (Dual-Core NVIDIA Denver 2 64-Bit CPU, Quad-Core ARM® Cortex®-A57 MPCore)

Ø  8GB RAM (128-bit LPDDR4 @ 1866Mhz |  59.7 GB/s)

Ø  256-core NVIDIA Pascal GPU, Ubuntu 18.04, CUDA 10.0.326 + tensorflow-gpu1.14

Figure 4. Jetson TX2 [1]


[1]: https://developer.nvidia.com/embedded/jetson-tx2

Prof. Bagchi leads the IoT and Data Analytics thrust of the $39M WHIN project (2018-23). We have IoT deployments in experimental farms as well as production farms around Purdue plus deployment on Purdue campus. The farm deployments are measuring temperature, humidity, soil nutrient quality, etc. while the campus deployments are measuring temperature, barometric pressure, and humidity. These are a unique resource for us to experiment with our protocols at scale and under real-world conditions.

Figure 5. IoT workflow for our digital Agriculture theme of the WHIN project

Sensing: Nitrate  sensor scale up manufacturing (+ phosphate, pesticides, microbial activity, …), Soil moisture, temperature Decagon sensors.

Communication: Optimized long-range wireless networking using LoRa, optimized short-range wireless networking using BLE, Mesh routing

Analytics: On-sensor such as threshold matching, On-edge device such as ARIMA, On-backend server such as LSTM

Deployment: Farms in Tippecanoe, Benton counties, including TPAC and ACRE

Figure 6. The hardware platform designed by us: (a) Motherboard PCB and battery holder with its packaging, (b) Motherboard PCB with two daughter boards, (c)the HMAA-1220 module


Figure 7. Campus-wide live experimentation testbed of a wireless mesh network

In the campus-scale deployment, we placed 13 LoRa nodes, distributed in a 1.1 km by 1.8 km area of Purdue University campus. All 13 nodes are deployed and continuously operated when experimentation is needed. We have received authorization from campus police for this deployment and there is signage at all the nodes to indicate that these are for research. The figure shows the complete map of our campus-scale experiment where a complete mesh network is established. Each blue dot represents a network node which are randomly and evenly distributed across the entire Purdue campus. The red node represents the location of the center node. The green dot represents the receiver, a laptop connected with SX1272DV K1CAS (LoRa development kit) from Semtech. Each solid line represents the actual LoRa link for the deployed network and the dotted line represents available LoRa links that were not being used. The node junction represents two nodes (node 12 and node 13) that were deployed on purpose at close range and were communicating via ANT instead of LoRa. In addition, three paths that are highlighted represent three distinguished data flows that are formed by the mesh network. For instance, path number 1 represents the path 9 ® 8 ® 7 ® 1. All nodes (including the center node) are located 1 meter above ground level and the receiver is placed on the 3rd floor inside of an office building facing south-east. The furthest node is placed 1.5 km away from the receiver and across more than 18 buildings in between.


Researchers at DCSL have access to piezoelectric sensors and MEMS sensors that measure changes in pressure, acceleration, temperature, strain. The sensors vary in sampling rate (10Hz with MEMS, 3.2kHz with the piezoelectric sensor).  DCSL has been conducting experiments with a motor testbed (shown in Fig. 5) to collect machine condition data (i.e., acceleration) for different health conditions. This data is currently being used for defect-type classification and learning transfer tasks in our research work.


A desktop computer sitting on top of a desk

Description automatically generated

Figure 8. A motor testbed equipped with sensors for measuring vibration at all frequencies

A picture containing indoor, table, sitting, black

Description automatically generated

Figure 9. Pizoelectric and MEMS sensors mounted on the motor testbed



The laboratory is equipped with a variety of high-end mobile and wearable devices, supported on Android and Wear OS architecture respectively. These devices help us in our ongoing mission to improve the overall reliability of mobile and wearable platforms. Table 2 and Table 3 provide details on the mobile and wearable device models available in the Lab.


Table 2. Smartphone Models.



CPU / Memory



Nexus 6P

Snapdragon 810, 3GB RAM, 32 GB storage

Fingerprint (rear-mounted), accelerometer, gyro, proximity, compass, barometer.


Nexus 5X

Snapdragon 808, 2GB RAM, 32 GB storage

Fingerprint (rear-mounted), accelerometer, gyro, proximity, compass, barometer.



Snapdragon 450, 3GB RAM, 32 GB storage

Fingerprint (front-mounted), accelerometer, gyro, proximity, compass.



Table 3. Wearable Device Models.




CPU / Memory



Moto 360

Quad-core 1.2 GHz Cortex-A7, 4GB

Accelerometer, gyro, heart rate


Watch 2

Quad-core 1.1 GHz Cortex-A7, 4GB

Accelerometer, gyro, heart rate, barometer, compass


Sport Smartwatch

Snapdragon Wear 3100 SoC, 4GB

Accelerometer, gyro, heart rate, light, compass/magnetometer,  vibration/haptics


Last modified: July 13, 2021