A Senior Design Project: Heating and Cooling System for Car’s Interior

This paper describes the design and implementation of a senior project involving a car heating and cooling system. During the summer and winter times, for cars parked outside, the interior temperature can become very high or very low causing discomfort for the driver and passengers. Therefore a device is needed to keep the vehicle interior at comfortable temperatures while standing on the parking lot or on the driveway. The goal of this project was to build a light weight compact car heater and cooler. The car heating and cooling system allows car users to maintain a reasonable temperature while sitting at home or in a parking lot. The designed system can fit in a back window. The system runs using a 12V DC power source powered through a solar panel that is mounted on the back window of the vehicle. This location was chosen because the exposure to light is greater in the rear and allows the solar panel to recharge faster and more efficiently. All components used in this system are rated 12VDC, with the exception of the microcontroller; an additional 5V DC regulator is used to power the Arduino microcontroller. Using a thermistor, the microcontroller tracks the temperature inside a vehicle. When a high temperature (i.e. temp > 70°F) condition is detected by the thermistor, the microcontroller l enable s a power relay to apply power to both the fan and the cooling element, based on a peltier and heat sink. This process continues until the temperature is within the specified range (i.e. 66°F ~ 70°F) or until user disables the system. In the same manner, when a low temperature (i.e. temp < 66°F) is detected by the microcontroller through the thermistor, a power relay is enabled to apply power to both the fan and the heating element, also based on a peltier and heat sink. This process continues until the temperature is within the specified range (i.e. 66°F ~ 70°F) or until user disables the system. As an additional feature, an air freshener pump is also included in the system that can be activated at 30 minute intervals and will continue until user disables the system. All features and temperature measurements are tracked and displayed on the LCD which is connected to the Arduino microcontroller. The paper covers the details of the design of hardware and software components of the system. I. DeVry University’s Senior Project Capstone Course Sequence DeVry University’s Electronics Engineering Technology program senior project is a four session course sequence in which students synthesize knowledge and skills learned in the previous courses. In the first course (ECET-390 Product Development), students research, plan and develop a project proposal. In the next three courses (ECET-492/493/494), Senior Project Laboratory) students implement the project plan by building and testing a prototype. A typical project involves a solution to a software/hardware based engineering problem. The process of developing and implementing a solution to the problem offers a learning opportunity for students to gain new insights and competencies as a result of “constructivist” and “deep learning” teaching/learning approaches. II. Project Background During the summer and winter seasons, for cars parked outside the cabin temperature can become be too high or too low thus making it difficult for drivers to sit comfortably in the cars to operate them. This paper presents a solution to this problem. The designed project keeps the interior of a car at a comfortable temperature while the car is parked in parking lot or on the driveway. III. What is presently available in the Market? Similar devices are available in the market but have following limitations: Solar cooler powered fans and battery powered heaters have drawbacks. o Small and inefficient, can’t cool/heat entire car o Do not have temperature sensors Devices that use the vehicle’s battery are not recommended as the battery can die if the device is left on for a long time. o Devices that use batteries are expensive to maintain. o Fans will only blow around the hot air inside the vehicle. IV. Project Objective The objective of this project is to design and implement an effective and inexpensive system to safely heat up or cool down the interior of a compact car when it is parked in parking lot or on a driveway. The designed system will be compact and easy to install with a self-sufficient power supply from a solar panel.