# Automated and Controlled System for Analysis of Residual Limbs Thermograms of Transtibial Amputees
## 2 Problem Statement
#### System Requirements  
To set the requirements for the cabin, first, we review the actual process for the capture. Figure 1a depicts the markers on the floor to fix a tripod with the thermal camera, take the picture, and then change it to another position. This task is time-consuming and depends on the user collocation of the camera, which affects the thermograms. Figure 1b shows the manual thermal snapshot of the residual limb of an amputee. In the picture, the background noise can be noticed. The actual thermal image processing and analysis of the residual limb are part of a set of tests performed to obtain a comfort factor and evaluate the quality of sockets for transtibial prostheses. The selection of participants for the trials has an inclusion criterion to have a homogeneous population. The selection and all the tests, including thermography, are part of a clinical trial approved by an ethics committee (PR2021-01). Two male subjects were the participants to test the image processing and analysis proposed for the automated system; Figure 2 shows one of the subjects in the manual process for thermography. Based on the actual issues for the manual process, the following requirements were established. _(1) General system requirements:_ **(a) process time,** the translation of the camera from start to end and the capture time of all samples is not greater than two minutes; **(b) positions,** the camera takes a clean capture every 90 degrees at least and has the possibility to take more steps if necessary; **(c) control,** the system has a microcontroller to manage the  
Figure 1: Issues to consider in thermographic analysis. **(a)** Setup for camera position. **(b)** Thermogram with background noise. Figure 2: Manual capture of the thermal image for a transtibial amputee subject. camera trajectory and the image capture; **(d) isolation,** the cabin reduces noise from the environment. _(2) Design requirements:_ **(a) exterior,** the device has an outer surface that prevents light from getting inside without increasing the inner temperature; **(b) portability,** the system can be deployed with ease in a time of five minutes approximately by two adults, and in the same way it can be undeployed; **(c) radial distance,** a constant radial distance of 45 cm through the entire process to avoid loss of focus; **(d) interface,** the cabin has an orifice in the middle of the upper part where the residual human limb is placed; **(e) height,** the height of the camera can be adjusted to compensate height variance due to the seat or the proportions of the participant. _(3) Hardware requirements:_ **(a) light,** the system has a light that indicates that the process of capture is in progress; **(b) power button,** the system has a button that energizes the device; **(c) power source,** the system has a power source that supplies the necessary voltage in direct current for sensors, actuators, and microcontroller; **(d) actuator,** the cabin has a DC motor to move the mobile platform with the camera through a rail. _(4) Software requirements:_ **(a) camera movement,** camera movement in the mobile platform is smooth, avoiding balance loss and sudden movements; **(b) velocity,** the platform of the camera moves with a smooth velocity, **(c) image capture,** image capture is performed every step of the moving platform: for the actual process at least every 90 degrees, but if the number of steps changes, the automated capture in each step is required; **(d) image processing and analysis,** the processing of the thermal pictures to obtain the average skin temperature of the subjects and the standard deviation; **(e) interface,** the system has an interface to adjust the movement and position of the camera, making desirable the automated and manual modes for movement and capture, **(f) programming language,** the software for the functionality of the device does not need the execution of additional software. After defining the system requirements, it is much easier to visualize a sketch design of the cabin.