Evaluations of Car and Trip Sharing Systems

Providing services at customers’ homes in urban city center is a challenging tasks. Congestion leads to high uncertainty in travel times and even if finally one arrives at his/her destination, the difficulty may have only just begun as one could end up circling the area multiple times to find an available parking spot. Consequently, substanitial amounts of working time is lost. To deal with such settings, companies can implement car sharing and trip sharing strategies.

As a sample setting, let’s again refer to the home health care industry, where nurses visit clients at their homes. As multiple services are time-critical, e.g., the administration of insulin injections, delays are not only costly, but furthermore have a major impact on service quality. In a recent publication, three different strategies to deliver services in urban settings challenged by limited parking spaces where numerically compared.

Separate vehicles

This is the most common form of delivering services. Each staff member has their own vehicle (in most cases cars). Consequently, at each visit, parking spots have to be found. Travel times are often short as vehicle routes are highly optimized, further leading to low average vehicle utilization. Nevertheless, the high flexibility of the system is a major advantage.

Car sharing

As not every staff member owns a vehicle and operating a large vehicle fleet for the providers is costly, car sharing systems can be implemented. In such a strategy, multiple staff members share a single vehicle, however, not at the same time. For instance, staff member ‘A’ uses the vehicle in the morning and parks the vehicle close to a public transport hub at the end of the shift. From this position, staff member ‘B’ takes the vehicle to use it for the afternoon shift. Consequently, less vehicles are required and utilization is increased. Nevertheless, parking spots at the customers’ premises still have to be found.

Trip Sharing

With trip sharing, multiple staff members use a vehicle at the same time. In the presented work, a system with dedicated drivers is assumed. These drivers pickup and deliver staff members based on requests, basically acting as a flexible shuttle service operated by the home service provider. The main advantage of trip sharing is that no parking spots at customers are required as the vehicle can simply momentarily pull off to the side of the road to load and unload staff members.

Results

The evaluation shows the impact of each strategy on driving durations and the number of required vehicles. It discusses the sustainability of the different mobility concepts and further investigates the performance of each concept in different geographic settings and under different objectives of decision-makers. Solution procedures to solve the corresponding optimization problems are introduced. As the results show, both car and trip sharing enable providers to substantially  reduce the vehicle fleet size. If parking spots are rare, trip sharing is beneficial, however, driving distances are prone to increase due to additional pickups and detours. Most importantly, to secure future service quality and successful implementations, substantial additional work is required to investigate the concepts given the various perspectives of all involved (e.g., staff members, customers, providers, policy-makers, public) and in real-life settings.

Thanks to support of the University of Natural Resources and Life Sciences, Vienna, this recent work was published under open access license. If you would like to read the full article, just download the publication and contact us in case you have any comments or feedback.

Reference:
–          Fikar, C, Hirsch, P (2017) Evaluation of trip and car sharing concepts for home health care services. Flexible Services and Manufacturing, in press. [Download Publication]
–          Fikar, C, Hirsch, P (2017) Home Health Care Routing and Scheduling: A Review. Computers & Operations Research 77, 86-95. DOI http://dx.doi.org/10.1016/j.cor.2016.07.019
–          Fikar, C, Juan, AA, Martinez, E, Hirsch, P (2016) A discrete-event driven metaheuristic for dynamic home service routing with synchronised trip sharing. European Journal of Industrial Engineering 10(3), 323-340. DOI: http://dx.doi.org/10.1504/ejie.2016.076382
–          Fikar, C, Hirsch, P (2015) A matheuristic for routing real-world home service transport systems facilitating walking, Journal of Cleaner Production 105, 300-310. DOI: http://dx.doi.org/10.1016/j.jclepro.2014.07.013

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